A COMPOSITE INDEX FOR ENHANCING SUSTAINABILITY WITHIN PUBLIC HOUSING PROJECTS IN LIBYA A Thesis Submitted in Partial Fulfilment of the Requirements of Salford University for the Degree of Doctor of Philosophy ABUBEKR MOHAMED ALI 2019 School of Built Environment
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A COMPOSITE INDEX FOR ENHANCING
SUSTAINABILITY WITHIN PUBLIC HOUSING
PROJECTS IN LIBYA
A Thesis Submitted in Partial Fulfilment of the Requirements of Salford University
for the Degree of Doctor of Philosophy
ABUBEKR MOHAMED ALI
2019
School of Built Environment
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Content
Content……………………………………………………………………………………………………... ii
List of Figures….………………………………………………………………………………………... vii
List of Tables…...………………………………………………………………………………………… ix
Acknowledgments……………………………………………………………………………………... x
Declaration………………………………………………………………………………………………... Xii
Dedication.…………………………………………………………………………………………………. xiii
Abstract……...……………………………………………………………………………………………… xiv
Figure 1.1: The Research Methodology Flow Chart ................................................................... 9 Figure 1.2: The Structure of the Thesis ......................................................................................... 13 Figure 2.1: World Population Growth, 1750-2100. ................................................................ 16 Figure 2.2: Global Total Material Use by Resource Type, 1900–2009. .......................... 18 Figure 2.3: The Average Daily Temperatures by Continent. ............................................. 19 Figure 2.4: Annual Fossil CO2 Emissions by Continent. ....................................................... 20 Figure 2.5: Fossil CO2 Emissions by Continent in 2017. ...................................................... 21 Figure 2.6: Countries Which Will Be Most Affected by Rising Sea Levels. ................... 22 Figure 2.7: Environmental Impact through the Life Cycle of Building Project. ......... 29 Figure 2.8: Factors Affecting SAM’s Appropriateness ........................................................... 43 Figure 3.1: Libya’s Location................................................................................................................ 49 Figure 3.2: An Example of Traditional Houses .......................................................................... 54 Figure 3.3: An Apartment Complex in Libya .............................................................................. 55 Figure 3.4: A Typical Villa in Libya.................................................................................................. 55 Figure 3.5: Housing Provision in Libya. ........................................................................................ 56 Figure 3.6: Libyan Electricity Consumption/Population. .................................................... 60 Figure 3.7: Libyan Natural Gas Consumption. ........................................................................... 60 Figure 3.8: Libyan Water Resources Distribution ................................................................... 61 Figure 3.9: Libyan CO2 Emission/GDP. ........................................................................................ 62 Figure 3.10: The Countries with the Most Road Traffic Death. ......................................... 64 Figure 3.11: Electricity Consumption by Sectors in Libya................................................... 68 Figure 3.12: Water Consumption by Sectors in Libya. .......................................................... 69 Figure 4.1: BREEAM’s Categories “The Code for Sustainable Homes” .......................... 81 Figure 4.2: BREEAM’s Rating System “The Code for Sustainable Homes” .................. 82 Figure 4.3: LEED’ Categories “Homes Design and Construction (v4)” .......................... 83 Figure 4.4: LEED’s Rating System for Homes Design and Construction (v4) ............. 83 Figure 4.5: GBCA’s Categories “Design & As Built v1.2” ....................................................... 84 Figure 4.6: GBCA’s Rating System “Design & As Built v1.2”................................................ 85 Figure 4.7: DGNB’s Categories “New Residential Building (NWO)” ................................ 86 Figure 4.8: DGNB’s Rating System “New residential building (NWO)” ......................... 87 Figure 4.9: The Performance of the Four SAMs over the Seventh Categories ........... 89 Figure 5.1: Relationship between Methodological Research Components ................. 96 Figure 5.2: Nested Research Methodology Model. .................................................................. 96 Figure 5.3: Saunders’ Research Onion. ......................................................................................... 97 Figure 5.4: Research Strategies Incorporated into Philosophical Stances. ...............111 Figure 5.5 The Six Step Process Thematic Analysis. .............................................................129 Figure 5.6: The Methodological Design ......................................................................................133 Figure 5.7: Research Process ...........................................................................................................134 Figure 6.1: A Model for Sustainable Homes Raised through the Focus Group ........152 Figure 6.2: LSHAM Model ..................................................................................................................216 Figure 7.1 Mechanism of Developing the Sustainability Composite Index ...............221 Figure 7.2: The Flow Chart of the AHP Process ......................................................................222 Figure 7.3: A Simple Hierarchy Framework .............................................................................226 Figure 7.4: LSHAM Rating Benchmark ........................................................................................237 Figure 7.5: The Process of LSHAM ................................................................................................238
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Figure 8.1: LSHAS Software – An example of Assessment Result Sheet .....................259 Figure 9.1: Research Journey ...........................................................................................................262
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List of Tables
Table 2.1: The key 17 Sustainable Development Goals ....................................................................... 26 Table 4.1: The Various SAMs round the world ........................................................................................ 78 Table 4.2: An Integrative Data Analysis Scheme of the Four Models’ Categories ................... 88 Table 4.3: An Integrative Data Analysis Scheme of the Four Models’ Criterions .................... 90 Table 5.1: The Five-Likert Scale and its Values Assigned ................................................................ 130 Table 6.1: Profile of the Focus Group Participants.............................................................................. 137 Table 6.2: Standing Dialogue for the Emergent Criterions Raised from Focus Group....... 150 Table 6.3: Reliability Statistics from the Pilot Questionnaire ........................................................ 155 Table 6.4: Questionnaire Responses .......................................................................................................... 158 Table 6.5: Summary of Demographic Data of Questionnaire’s Respondents ......................... 159 Table 6.6: Cronbach’s Alpha test for Reliability ................................................................................... 162 Table 6.7: The Measures of Central Tendency for the Set of Categories .................................. 163 Table 6.8: The Measures of Central Tendency for Management & Process Criteria........... 164 Table 6.9: The Measures of Central Tendency for Material Efficiency Criteria..................... 165 Table 6.10: The Measures of Central Tendency for Energy Efficiency Criteria .................... 166 Table 6.11: The Measures of Central Tendency for Water Efficiency Criteria ...................... 167 Table 6.12: The Measures of Central Tendency for Waste & Pollution Criteria ................... 168 Table 6.13: The Measures of Central Tendency for Health & Wellbeing Criteria ................ 169 Table 6.14: The Measures of Central Tendency for Location Quality Criteria....................... 170 Table 6.15: Categories and Criteria Defined through the Questionnaire Survey ................. 171 Table 7.1: The Fundamental Scale of Absolute Numbers ................................................................ 223 Table 7.2: List of Experts Involved in the AHP Exercise ................................................................... 228 Table 7.3: Consistency Ratio Measured for AHP .................................................................................. 229 Table 7.4: Combined Pair-Wise Comparison Matrix of Management & Process Criteria ........ 230 Table 7.5: Combined Pair-Wise Comparison Matrix of Materials Efficiency Criteria .............. 231 Table 7.6: Combined Pair-Wise Comparison Matrix of Energy Efficiency Criteria................... 232 Table 7.7: Combined Pair-Wise Comparison Matrix of Water Efficiency Criteria .................... 233 Table 7.8: Combined Pair-Wise Comparison Matrix of Waste and Pollution Criteria ............. 233 Table 7.9: Combined pair-wise comparison matrix of Health and Wellbeing Criteria ...... 234 Table 7.10: Combined Pair-Wise Comparison Matrix of Location Quality Criteria .................. 235 Table 7.11: The weighting System Developed through the AHP Technique .......................... 236 Table 8.1: Different Techniques for Validating a Model ................................................................... 249 Table 8.2: Validation Interview Agenda ................................................................................................... 251 Table 8.3: Profile of the Validation Participants................................................................................... 252
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Acknowledgments
Though this thesis is assigned solely to my name, many people and organisations
have contributed to its production. Therefore, this is a great opportunity to express
my sincere gratitude to all those who helped this research to see the light.
First, thanks, with all praise to God, for granting me with the effort to make the
completion of this thesis possible.
I owe an immense debt of gratitude to my supervisor Doctor Anthony Higham; whose
doors have always been open to me, despite battling with overwhelming teaching and
research work. Without his unwavering support and encouragement, and his ability
to keep his wits together, this doctorate would never have been started or completed.
He gave me the freedom to pursue an interesting path, and his advice, experience, and
knowledge have been invaluable throughout.
Not forgetting, my ex-examiners Professor Carl Abbott and Mr Andrew Fleming, who
assessed the Interim Report, your meaningful comments have greatly influenced and
reoriented my research to what it is today. I also owe a big thanks to Dr Amanda
Marshall-Ponting, who assessed the Internal Report, together with Dr Paul Coates,
whose invaluable pieces of advice were beyond helpful and aided the progression
that has been made in this study. After successfully getting passed my viva, I would
like to recognise the efforts and time paid from Dr Yingchun Ji (Internal Examiner)
and Dr Zaid Alwan (External Examiner – Newcastle University), I have been honoured
to be awarded the PhD degree by you, it was unforgettable moments in my life.
I am also so grateful to all the people who participated in this research and gave their
time, thoughts, and opinions, and allowed their stories to be told, thank you very
much with all my sincere gratitude and respect.
I gratefully acknowledge the enduring help from my friends Wail, Othman and Aisha
who were great guides for my journey. I would also like to thank Dr Jamal Galley from
the Libyan Institute of Architects and Dr Yosef Kaplan from the Organisation for
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Development of Administrative Centres, thank you very much for your help and
support.
Last but certainly not least, I wish to express my heartfelt gratitude to my lovely
Mum, words of appreciation are not enough to express my feelings towards her, as
she has always prayed for me to achieve the success I was looking for. Special warm
thanks go to my wonderful wife and my beautiful children, joy and love, for their
sincere and endless love. I cannot also forget to assign special regards to my brothers
and sisters for their immense encouragement and support, without you all I could not
be as I am.
Finally, I would like to send special thanks and acknowledgment for all the financial
sponsorship that was gratefully received from both the Libyan Ministry of Housing
and Sirte University, the place where I have always found respect and appreciation.
Abubekr Mohamed Ali
2019
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Declaration
I declare that the research contained in this thesis was carried out by me. This work
has not been previously submitted either in part or full for any other award than the
degree of Doctor of Philosophy in Built Environment at University of Salford.
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Dedication
Dedicated
To the loving memory of my late Father
Mohamed
To my Mother
Omassaed
To my Wife
Ibtisam To my Children
Mohamed, Maha, Salma, Rahma & Habiba And
To my Loved Ones
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Abstract
The attention on sustainable homes is driven by the desire to use more
environmentally friendly products, that are aligned with sustainable technologies and
which improve the health and wellbeing of the occupants, whilst attributing to the
reduction of house building costs over a life cycle. It is widely acknowledged that
sustainable homes should satisfy the overarching principles of sustainability, fitting
in with the local influences of the regional specialities they are built in. The ambition
of the Libyan government for imbedding sustainability within the construction
industry could benefit greatly from such a rigorous set of sustainability assessment-
based criteria that aid to design, evaluate and monitor the desired development. The
aim of this study is to develop a sustainability-based index of multi-criterion to assist
Libyan public home projects in addressing sustainability issues in their activities and
strategies. It is argued that well-known sustainable assessment methods are not
designed to be used in various countries including Libya. Therefore, this study seeks
to investigate the appropriateness of using these methods to integrate their
commonalities and establish a new scheme of building sustainability-based criteria
for the Libyan context. To achieve the aim of this study a variety of research methods
and techniques within a triangulated approach have been adopted. These included
(1) a focus group interview; (2) a wide questionnaire survey; and the (3) Analytical
Hierarchy Process Method (AHP). The components of the developed model were
derived from a thorough analysis of data collection obtained from a variety of sources
including practitioners and professionals from contractors, the Libyan government,
industry, and academia. A triangulation approach has been utilised within and across
the methods and techniques adopted. It has facilitated access to different levels of
reality, through the combination of qualitative and quantitative methods. The
sustainability-based index that has been developed through this research is
composed of 43 criteria, grouped into 7 main categories. Water efficiency ranked at
the top with 32 credits, reflecting Libyan crisis due to water scarcity. Whilst Libya has
alternative and abundant natural energy resources (i.e. so-lar energy, wend, etc.).
This has made energy efficiency issues at the second highest priority (24 credits),
which can encourage the adoption of more sustainable, renewable energy resources.
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Fundamentally, it provides a clear vision of what needs to be addressed and what
would enable the achievement of sustainable homes in Libya. Validation has been
conducted through a review of the results obtained on the journey of this research.
Utilising a group of local and international experts, who have been selected based on
their knowledge in sustainable housing and the construction profession, thus
providing the basis for a more successful formula and a final model of sustainable
housing for the Libyan context. The contribution of this study to the existing body of
knowledge is threefold: (i) academic, through addressing significant research
questions that have not been addressed before and providing an evidential base of
the findings; (ii) procedural, through the development of a comprehensive model to
assist Libyan home projects in better addressing sustainability aspects in their
activities and strategies; and (iii) methodological, through the use of triangulation,
which construction management research have been reluctant to use in the past, and
through the provision of a comprehensive review, successful application and a clear
demonstration of the use of focus group interviews and questionnaire methods.
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1 Overview of Research
1.1 Chapter Overview
This is an initial part of this thesis, putting the study into context by exploring the
background and emphasizing the need for the research. An articulation of the research
problem is followed by the identification of the aim and objectives of the study. The
significance of this research in light of its originality and potential contributions is
rationally raised. Finally, this section highlights an overview of the methodological
design that has been adopted for its implementation.
1.2 Research Context
The world is rapidly changing, with emerging critical calls concerned with inertia in our
ecological systems and the unreadiness to deal with complex and uncertain-based
challenges. Specifically, core environmental problems include resource degradation,
climate change and global warming, air pollution, the scarcity and pollution of fresh
water, flooding and pollution of the world's seas and oceans. According to a 2014 report
published by the United Nations Department of Economic and Social Affairs (UNDESA),
3.9 billion people, or 54% of the global population, live in cities, and by 2050, two-thirds
of the global population will be living in cities. Most of this growth is happening in
developing countries, which have limited capacity to deal with this rapid change (UN,
2015; 2012). Where increasing mainstream steps towards achieving high levels of living
standards and economic growth that have characterised the industrial era, have
negatively affected the surrounding environment through resource depletion and
energy consumption (IPCC, 2018). Notably, climate change is one of the most pressing
global challenges that countries face today, threatening human life on the planet. As
IPCC’s (2018) report estimated, anthropogenic global warming has recently risen at
approximately 0.2°c per decade due to industrial emissions. Furthermore, there is
evidence that the construction industry consumes a massive portion of natural
resources and energy. Global material use is estimated to increase almost tenfold since
1900, accelerating from an annual growth of 1.3% in 1900–1949, to 2.6% in 1950–
1999, and 3.6% annually in 2000–2009 (Krausmann et al. 2009). Currently, according
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to Worldwatch Institute (2003), construction activities, globally absorb approximately 3
billion tons/year of raw materials, constituting 40% of the total annual use. It also
consumes nearly 25% of the harvested wood and more than 15% of the fresh water.
This tremendous consumption of available resources will undoubtedly exacerbate
global environmental problems if radical changes do not urgently take place. These
sustainability-related problems can be identified as interdependent and release serious
challenges that are shaping our future (RIBA, 2014). Therefore, radical shift is inevitably
required to reorient our thinking and shape a new paradigm of change that ensures
sustainability of the available resources and protects our environment from the
threatening hazards. It is of utmost importance to take prerequisite actions to avoid
severe consequences that are likely to happen to the current and future generation.
In this respect, the developing countries’ situations are even worse according to the
International Energy Agency (IEA, 2017), and to a large extent, this can be traced back
to a lack of a sustainability-led paradigm shift, that is able to monitor and guide the
industry to ideal performance (Tupenaite et al., 2017; Cole & Jose Valdebenito, 2013;
Sev, 2011). Subsequently, the importance of a Sustainability Assessment Method (SAM)
is fundamental in order to incorporate sustainability interventions into the built
government regulation and policy; 5) understanding of construction stocks; and 6)
understanding of the culture value and public awareness (Mao et al., 2009; Ding, 2008;
Cole, 2005: 1998). Possible development routes for future generations of sustainability
assessment tools for built environment as argued by Ding (2008) and Fenner and Ryce
(2008), include the importance of expanding the assessment to include both social and
economic indicators, thereby developing a complete sustainability assessment system.
Nevertheless, it is evident that there is a lack of research on the selection of criteria
related to sustainability in Libya’s construction investments. Despite calls from
academia (Elgadi et al., 2016; Shawesh, 2016; Shibani & Gherbal, 2016; Ahmed et al.,
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2015; Gherbal, 2015) for a paradigm shift away from the scheme limited to the
assessment of economically driven approaches, overarching sustainability-led
assessment systems are still rarely used. As Ahmed et al. (2015) point out, it is essential
for the industry to have regular evaluations and assessments, thereby allowing the
collation of evidence related to changes and impacts which might affect the
environment. Ultimately, moderating these impacts in order to develop the quality of
building practices. Although, extensive studies (Elgadi et al., 2016; Mohamed, 2013;
Shebob 2012; Omran et al., 2012; Almansuri et al., 2009; Ismail et al., 2009) focus on a
wide range of developmental issues associated with the built environment in Libya, only
a few have addressed specific aspects relevant to building sustainability-related
features. For example, Quality Management and Environmental Management systems
were addressed through a study by Ismail et al. (2009) with the aim of applying an
integrated management system for assessing and monitoring the construction
processes and activity status in the Libyan building sectors. A study conducted by
Omran et al. (2012) developed a range of critical success factors that are most
important to the success of construction projects in Libya. In this study, feedback ability
was ranked first, followed by project monitoring, coordination effectiveness, design of
education organisation structures and decision-making effectiveness. Whilst Shebob’s
(2012) study focused on issues that are more likely to influence the success of building
projects through the investigation of delay factors affecting the Libyan construction
projects. Furthermore, an extensive study by Mohamed (2013), which focuses on the
phenomenon of urban fragmentation at neighbourhood level, which investigated
different urban typologies in the city of Benghazi. This study considered the main
characteristics of the sustainable city namely: urban liveability which includes designs
for thermal comfort and privacy intervention; accessibility represented by the level of
spatial connectivity and urban diversity; environmental sustainability measured by
embedded green solutions and a sense of ecological footprint. This study faced
limitations at different levels including its lack of focus on urban areas, instead
investigation of the physical form and the process of city building being aligned with
both landscaping and socio-economic and cultural aspects were essential to the idea of
sustainable development. A further study entitled ‘Do courtyard houses provide the
ideal climatic solution in hot climate regions?' was published by Almansuri et al. (2009).
The focus of this study was on sustainability-based solutions for architecture to reduce
5
energy consumption of houses, but there was also a tentative reference to some factors
related to sustainable homes. Including the need for achieving harmony with nature,
proper insulation and the shading of houses, harnessing natural ventilation and natural
light and green roofing as well as a few energy and water conservation measures.
Nevertheless, it is unfortunate that the recommendations of this broad study have not
been translated into action and the study lacked details and goals. More recently, a
study by Elgadi et al. (2016) identified a set of indicators for sustainable
neighbourhoods in Tripoli, Libya, reflecting economic, environmental, social, and
institutional dimensions. Indicators in this study were developed to measure progress
of the urban and community features, opposing the current study which is determined
to identify a sustainability-based tool for precisely assessing building projects in Libya.
The urgent need for research to investigate a set of standards for sustainable buildings
in the Libyan context has been emphasized by a number of authors including, Elgadi et
al. (2016), Shawesh (2016), Shibani and Gherbal (2016) Shebob (2012), and Almansuri
et al. (2009) who have corroborated previous studies from Ngab (2007), UPA (2006)
and El-Hasia (2005). Collectively this body of work strongly argues that sustainability-
based criteria of Libya’s buildings should be identified to assess their compliance when
benchmarked against the fundamental principles of sustainable development,
emphasising that there are a lack of specific policies and assessment tools that evaluate
and monitor the building. The absence of comprehensive frameworks and a lack of
assessment methods relevant to sustainability in building projects are what
interestingly motivate this study to address the topic of adjusting sustainability-based
criteria for dwellings in Libya. Consequently, this study has raised the argument that a
customised sustainability-based assessment method should be developed based on the
natural Libyan context. In this essence, the desired system should be designed in ways
that eliminate the weaknesses of the existing methods. This method needs to be
developed through a reliable process that ensures: (i) effective identification of criteria
and categories for the Libyan context; (ii) transparent set of a credit weighting system;
and (iii) sufficient prioritising of the components of the model.
Against this background, the rationale of this study can conclude that the leading global
sustainability assessment models (e.g. BREEAM; LEED) have neither been adapted to
the cultural, economic and political specificities nor the context of the Libyan built
6
environment. These constraints appear through a lack of attention to region-related
variations, including the availability of resources, the nature of local architecture,
certain environmental conditions, and other specific critical economic and socio-
cultural factors. By contrast, a review of the Libyan context has demonstrated that a
specific criteria and ranking system that assesses the extent to which Libyan buildings
satisfy the sustainability principles is quite absent, this study therefore, is an attempt to
fill these gaps for the Libyan Sustainable Homes Assessment Model (LSHAM).
1.4 Significance of the Study
Raising criteria is highly useful in planning sustainability when they are linked to
sustainability goals that are frequently set by policy makers as a reference to a level of
sustainability that must be satisfied in the future. This study aims to adjust a selection of
sustainable criteria for residential building in Libya. The findings of this study will help
the shift to sustainable homes in which design, operations and implementation are to be
modified on the basis of such criteria and standards. The value of the Composite Index
of sustainable homes lies in its potential to assist contractors in re-designing their
building projects with sustainability-based criteria in mind. This index can provide an
effective framework for decision-making processes in order to incorporate
sustainability principles into project processes by embedding sustainable design
priorities and setting appropriate sustainable design strategies for housing projects.
The customised tool can also be used as an assessment tool that helps to meaningfully
determine performance measures and reflect how well Libyan dwellings are prepared
for the sustainable built environment.
1.5 Purpose of the Study
The principle purpose of this study is to provide a decision support system that allows
the promotion of sustainable development in housing investments through the
development of a sustainability-based assessment method, thus enabling identification
of the most effective interventions and optimising performance in favour of maximising
the users’ satisfaction, environmental protection, and economic benefits.
1.5.1 The Aim
The centric aim of this study has been identified in light of the main purpose motivating
the researcher to conduct this study and is stated as follows: “To customise an applicable
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Composite Index for assessing Libya’s sustainable homes”. A specific range of objectives
was generated in order to rationally achieve the desired aim.
1.5.2 Objectives
Based on the centric aim, this study is determined to fulfil a fivefold objective which is
outlined below:
Obj.1 To critically review the perceived importance of sustainability together with
the current sustainability assessment methods for housing investments.
Obj.2 To analyse the categories and criteria of well-established sustainability-based
assessment methods to set the foundation for a new insight of a Composite Index.
Obj.3 To customise applicable categories and criteria that constitute the main
characteristics of sustainability in Libya's housing investments.
Obj.4 To determine the weighting coefficient that ensures prioritisation of its main
categories and criteria based on the specifications of Libyan context.
Obj.5 To refine the Composite Index of sustainable homes and provide
recommendations for further development.
1.6 Research Design and Methodology
The study focuses on the adaptation of a reliable sustainability-based Composite Index
for housing investments for the Libyan context, which is based on the groundwork of
well-established methods (i.e. BREEAM; LEED; GBCA; DGNB). In order to design this
model, care has been given to deliver applicable assessment categories and criteria and
an appropriate weighting system. To achieve the centric aim of this study, two major
stages are organised; the theoretical and empirical stages. Figure 1.1 below illustrates
the methodological structure of the study.
The theoretical stage consists mainly of: (i) a critical review of sustainability-based
assessment rating methods; (ii) a selection of well-established assessment models (i.e.
BREEAM; LEED; GBCA; DGNB); and (iii) an integrated analysis to determine the
commonalties and synthesize the criteria and categories for the theoretical framework.
This stage has the potential to provide an in-depth theoretical background for
8
developing a new model for sustainable homes in the Libyan built environment. The
identified components are assessed within the next stage.
The empirical stage was launched with a focus group interview, which recruited five
experts in the relevant sustainability field of sustainable homes in Libya. In order to
examine the current sustainability assessment applications in housing investments, as
well as investigating the most important sustainability interventions for sustainable
homes. A large-scale questionnaire survey is a principle method of the study, which
allowed engagement with a wide spectrum of practitioners, professors and
administrators, who are well-experienced in both the scientific community and the
practice field relevant to the context of Libya’s built environment. The questionnaire
technique structures the most applicable categories and criteria for assessment of
sustainability in housing investments. While an Analytical Hierarchy Process (AHP) has
been employed to provide a reliable weighting system, prioritising these categories and
criteria while taking into consideration the distinguishing specifications of the Libyan
built environment. Finally, this study employed a supplementary technique to validate
the proposed model. A small-scale interview with local and international academics and
professionals, was conducted with the aim of evaluating the Composite Index
developed. The research was then determined to develop a discussion and connect the
literature review and the findings from the focus group interview, questionnaire survey
and the AHP technique along with the results obtained from the validating interview. In
order to structure a robust Sustainability-based Composite Index for assessment of
Libya’s homes, and formulate meaningful findings and recommendations.
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Figure 1.1: The Research Methodology Flow Chart.
1.7 Research Scope
As mentioned previously, the general purpose of this study is to develop and support a
decision system for assessment of sustainability in the Libyan housing industry. This
includes the customisation and quantification of a range of criteria and categories that
present the most applicable sustainability interventions in sustainable homes.
Therefore, the study has been narrowed to the following scopes:
10
1. The study is focused on the identification of criteria that influences the Libyan
housing building industries, taking into consideration environmental, economic
and socio-cultural constraints.
2. Influencing criteria were found through integrated analyses of well-known
assessment methods, which were only used to identify and compare the possible
assessment criteria for Libyan housing projects.
3. The consultants were selected from the academia, industry and government
sectors, who were shown an adequate knowledge in the relevant subject and
from different regions across the state of Libya.
4. The HAP technique was used to analyse and quantify the proposed categories
and criteria, to establish a Composite Index for assessment of sustainability in
housing sectors.
1.8 The Added Value of the Study
The present study aims to contribute to the body of existing knowledge significantly,
with the aspect of sustainability-based assessment methods for housing investments in
the context of Libya (LSHAM). The most applicable categories and criteria of well-
known building assessment methods are considered as the basis of this study and
proposed to develop the structure of LSHAM. The study adopts a ranking system which
reflects the most applicable interventions relevant to sustainability in the Libyan built
environment context, involving a calculation procedure via a weighting coefficient, as
well as rating formulas that present a single result for the level of sustainability
embodied in the project.
Notably, the contribution of this thesis to the existing body of knowledge can be
determined threefold as: (i) Theoretical, through addressing significant research
questions that have not been addressed before and providing the evidence based on
these findings; (ii) Methodological, through the use of triangulation via the provision of
a comprehensive review, successful application and clear demonstration of the use of a
focus group interview and large-scale questionnaire; and (iii) Practical, through
development of a Composite Index to assist decision makers in better addressing
sustainable homes through consideration of the major features related to sustainability
in Libyan context.
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Research on sustainability-based assessment methods for Libyan dwellings is both
timely and responsive to frequent calls from researchers for improved progression of
the built environment in Libya, towards more environmentally, economically and
socially sustainable development. As a result, this work can be considered as a unique
attempt, undertaking a scope that has not been dealt with previously.
1.9 Thesis Layout
This study comprises of nine chapters (see Figure 1.2), a brief overview of the content of
each chapter is described as follows:
Chapter 1: Overview of Research
This chapter sets the rationale for the study, providing a general introduction to the
research. It includes a brief discussion of the subject matter, exploring the background
context and need for the study. The rationale of the research is then followed by
presentation of the core aim and objectives. It also highlights the added value and scope
of the study. Finally, it briefly visualises the research methodology and outlines a thesis
structure.
Chapter 2: Sustainable Development and Reflections on Construction
This chapter broadly considers the global threats facing humankind and the planet
before discussing the main agenda of sustainable development with a special focus on
sustainability in construction. Consideration is also given to the themes associated with
the home concept, including the definitions and influential factors of sustainability in
housing investments. Finally, potential research gaps have been identified after
reviewing the relevant efforts in the literature available.
Chapter 3: The Housing Industry in Libya
Chapter 3 seeks to highlight the Libyan context through an extensive literature review
by presenting a brief background about the state of Libya including topographic and
geographical features, the construction and housing industry and socio-cultural aspects,
aligned with the relevant challenges and constraints. It also highlights the main housing
types and provisions in Libya, following by exploration of a range of challenges facing
sustainable homes with some sustainability initiatives in the Libyan context.
Chapter 4: The Development of a Theoretical Framework for Sustainable Homes
This chapter highlights the main features of SAM including its principles, typology,
systems criteria and rating systems, followed by an overview of the prevailing SAMs
12
worldwide. It also presents an integrative data analysis of the well-established
sustainability assessment methods, in order to establish a theoretical model of study
that is intended to be developed further through the next stages.
Chapter 5: Research Design and Methodology
This chapter presents the methodological approach employed in this research. For this
purpose, the philosophical assumptions of research methodology and a justification of
the methodology adopted were explained. Then greater attention is given to the adopted
methods of the focus group interview and questionnaire survey. The selection of the
research sample and analysis techniques are addressed before highlighting the
triangulation and ethical considerations that took place.
Chapter 6: Data Analysis and Discussion
This major chapter provides analysis of the assessment categories and criteria derived
from the focus group and questionnaire survey results that were proven to be applicable
for Libyan sustainable homes. It discusses the main findings obtained through
triangulation of the results derived from the literature review, integrated analyses of
well-known SAMs, focus group interview results and the large-scale survey, in
confirmation with the main objectives, contribution, features and possible orientations
that can be recognised for each criterion. These categories and criteria are then utilised
to design the study’s model (LSHAM).
Chapter 7: Establishing a Weighting System for a Sustainability Composite Index
This chapter presents analysis and discussion of the findings in relation to the weighting
system, along with the credit allocation, rating formulas, and benchmark classification
that are employed in the developed model. This presentation concludes with a discus-
sion of the approved weighting system for the Libyan context, along with the distinctive
aspects of the LSHAM when compared to well-established methods and its added value
of practice.
Chapter 8: Validating the Developed Model
This chapter presents a final assessment of the developed index in order to obtain an
evaluation of the views of recognised experts to extend the discussion and provide a
critical understanding of the validation of the index. While also identifying other
possible refinements or possible directions for the research to enable its
implementation in practice.
13
Chapter 9: Conclusion
This chapter presents conclusions about the contribution, limitations and implications of
the study, and suggests recommendations for further research.
Figure 1.2: The Structure of the Thesis.
14
1.10 Chapter Summary
This chapter has presented the background, rationale, research aim, objectives and
methodology followed by outlines of the thesis structure. It has sought to provide an
overarching scene of the study along with a route map describing the research tasks and
developmental processes, whilst contextualising the study in order to highlight its added
value. In the next chapter, the main agenda of sustainable development will be
addressed before discussing sustainability in construction with a special focus on home
concept and its sustainability considerations are drawn.
15
2 Sustainable Development and Reflections
on Construction
2.1 Chapter Overview
Since the centric aim of the study is to understand and define a sustainable
development-based assessment tool for housing projects, it is of the utmost
importance to pay higher attention to the concept of Sustainable Development (SD) in
light of the sustainability agenda and the objectives beyond the appraisal process for
Sustainable Construction (SC). This has been addressed by aligning the discussion
with the need for shaping Sustainable Homes and the potential challenges associated
with SD in the housing sectors. With this in mind, the literature review is devoted to
responding to five principal questions that have been proposed to synthesize the
theoretical framework of the study. They are: (i) Why does SD exist? (ii) What does
SD mean and how is it perceived? (iii) Why is SC important and what are its key
features? (iv) How can the concept of Home be defined and what are its sustainability
considerations? And finally, (v) How can an effective assessment model be helpful to
deliver sustainability in the housing sector?
To answer these queries, this chapter has been presented through four wide lenses.
The first scope broadly considers the global threats facing humankind and the planet.
This leads to the discussion of the main agenda of sustainable development in the
second perspective. While, a special focus on sustainability in construction is
addressed through layer three. Finally, in the fourth lens, consideration is extensively
given to themes that are associated with the home concept, as deemed the central
focus in this study. This covers the definitions and influential factors of sustainability
in housing projects. The final axis is devoted to drawing out potential research gaps
that are planned to bridge this study throughout. It reviews the relevant efforts that
offer the most insight into sustainability appraisal techniques.
16
2.2 Changes Threatening the Global Environment
With the development of people’s living standards and the industrial revolution,
humans have drastically altered the ecological system. Although this development has
had a positive impact on human life in terms of an increased life expectancy rate and
well-being, population growth and natural resource depletion have ultimately led to
negative effects on the natural environment such as global warming and climate
change.
2.2.1 World Population Growth
One of the most obvious characteristics of human evolution and history has been the
exponential growth of the global population. As this growth continues, it will have a
significant impact upon every aspect of human existence from increasing demand on
natural resources to the proliferation of mega-cities and the infrastructural needs of
an increasingly urbanized world population. Figure 2.1 shows world population
growth between 1750 and 2100 (Ourworldindata, 2017).
Figure 1.1: World Population Growth, 1750-2100 (Source: Ourworldindata, 2017).
Historically, the number of global populations according to Ourworldindata (2017),
was approximately one billion in 1800, with an annual growth rate of 0.4%, and it
took one century to reach the second billion. The growth trend after that, increasingly
expanded, reaching three billion after 30 years in 1960. Only 15 years later, it arrived
17
at four billion, with the greatest annual growth rate of 2.1%. This number
dramatically increased to hit six billion by the end of the 20th century. In 2015, the
world population became 7.4 billion even though the annual growth rate decreased at
1.1%. Moreover, the world population is expected to be nine billion in 2050 and
eleven billion by the end of the ongoing century with an annual growth rate of only
0.1%.
One of the biggest challenges, according to a 2014 report by the United Nations
Department of Economic and Social Affairs (UNDESA), is that 3.9 billion people, or
54% of the global population now live in cities, and by 2050, two-thirds of the global
population will be living in cities, whilst most of this growth is happening in
developing countries which have limited capacity to deal with this rapid change (UN,
2015). This extraordinary increase in population has the potential to lead to further
pressure on resource consumption. This leads to added concern of another serious
issue, which is threatening the world today, that of resource depletion.
2.2.2 Natural Resource Depletion
Developments in scientific and technological knowledge along with tremendous
economic growth, have led to intensive exploitation of natural resources including
fossil fuels, materials, water and land, which have increasingly impacted on the built
environment. As Krausmann et al. (2009) point out, global demand for resources has
increased substantially since the start of the 20th century. While global material use is
estimated to increase almost tenfold since 1900, accelerating from an annual growth
of 1.3% in 1900–1949, to 2.6% in 1950–1999, and 3.6% annually in 2000–2009
(Krausmann et al. 2009). Notably, developing regions account for an increasing
proportion of global resource use. With Europe responsible for 19% of total resource
extraction in 1980 and the US accounting for 18%, both falling to 10% by 2009.
However, Asia’s share increased from 41% to 57% over the same period. Figure 2.2
shows the development in global use of construction materials, ores and industrial
minerals, fossil energy carriers, and biomass (Krausmann et al., 2009).
18
Figure 2.2: Global Total Material Use by Resource Type, 1900–2009 (Source: Krausmann et al., 2009).
Whilst global demand for natural resources is expected to grow increasingly in the
coming years, the outlook for supplies is more uncertain. Geographic concentration of
reserves in a range of nations is a serious concern since it affords suppliers greater
influence over global prices and supplies, as shown by the influence of the
Organization of Petroleum Exporting Countries (OPEC) over global oil markets.
Uncertainty regarding access to products goes up if reserves are concentrated in
politically unstable regions (EC, 2014). Certain non-renewable resources deserve
particular attention because of their economic relevance, including their role in
green-energy technologies. Significantly both Lelieveld et al. (2012) and Almasroui et
al. (2012) have stated that there is an intensive concern with regard to the
sustainability of these resources and the continuity of economic growth, since any
shortage in one will lead to severe global problems such as economic collapse and
rigorous environmental degradation. Accordingly, Paudel et al. (2014) have argued
that the construction sector can be considered as one of the most significant
achievements of modern civilisation in which people are quite likely to be healthier,
and life is easier and more comfortable. Nevertheless, exploitation of natural
resources through construction activities that consume a large amount of resources
have many life-threatening side-effects, including stratospheric ozone depletion, air
pollution, water pollution and deforestation (Jain, 2013). This tremendous
consumption of natural resources has the potential to lead to further pressure on the
19
global ecosystem. Thus, it has brought concern to a further serious problem
threatening the world today, which is global warming and climate change.
2.2.3 Climate Change
Human activities are estimated to have caused approximately 1.0°C of global
warming above pre-industrial levels, which is expected according to IPCC (2018), to
hit 1.5°C between 2030 and 2052 if the current rate continues to accelerate. In many
regions worldwide, warming temperatures greater than the global annual average
have been recorded, particularly in the Arctic which is likely to reach three times
higher. As IPCC’s (2018) report states, estimated anthropogenic global warming has
recently risen at approximately 0.2°c per decade due to ongoing emissions. The
graphs in figure 2.3 show the average daily temperatures in four continents
(Worlddata, 2017). It can already be seen quite clearly that there has been a high rise
in temperatures worldwide since the 1980s. Especially noticeable are the
developments in Europe, North America and Asia, where there are considerable
temperature increases.
Figure 2.3: The Average Daily Temperatures by Continent (Source: Worlddata, 2017).
20
Even though the degree of temperature has increased worldwide along with
increasing natural disasters such as tsunamis and earthquakes, the underlying causes
beyond these conditions are likely to be unpredictable (Lelieveld et al., 2012). In this
regard, the 2018 Intergovernmental Panel for Climate Change’s (IPCC) report
confirmed that the greenhouse impact and the increased atmospheric concentration
of CO2 were the main reasons for climatic change (IPCC, 2018). Moreover, the report
also claims that human activities such as burning fossil fuels, oil, coal and gas produce
high amounts of CO2 emissions, which can be considered as the major cause of both
global warming and climate change. According to Global Carbon Project (GCP),
approximately 33% to 50% of the total land surface has been altered by human
development, whilst the concentration of CO2 in the atmosphere has risen to about
40% primarily through the combustion of fossil fuels (GCP, 2018). The GCP’s report
indicates that Asia has dominated global CO2 emissions since 2000, whilst its figure
(excluding the Middle East) was 16.9 billion tons in 2017, accounting for 54.2% of
global CO2 emissions. Figures 2.4 and 2.5 show annual fossil CO2 emissions by
continent particularly in 2017.
Figure 2.4: Annual Fossil CO2 Emissions by Continent (Source: GCP, 2018).
21
Figure 2.5: Fossil CO2 Emissions by Continent in 2017 (Source: GCP, 2018).
The expected consequences of global warming are destructive leading to melting ice
caps that have the potential to expand the oceans and increase sea levels (Lelieveld et
al., 2012). Moreover, impacts on the natural and human systems from global warming
have already been observed, whilst many land and ocean ecosystems have already
changed as a result. Some of these impacts seems to be long-lasting or irreversible,
such as the loss of some ecosystems. For example, the sea level rises roughly 6
cm/decade for each temperature rise of 1.5 to 5.5°c, which is expected by 2100 to rise
approximately 50 cm. This means that many coastal cities and inhabited islands will
be affected (Strauss et al. 2015). Notably, according to the 2015 Climate Central’s
report, China will be most affected by rising sea levels caused by global warming. The
report assesses the impact of sea level rises caused by 2 and 4 degrees Celsius global
temperature increases. Figure 2.6 shows the 2010 population - in millions - who will
be affected by the median locked-in sea level rise from the two different temperature
increases (Strauss et al., 2015).
22
Figure 2.6: Countries Which Will Be Most Affected by Rising Sea Levels (Source: Strauss et al., 2015).
As shown in Figure 2.6 above, the list is strikingly dominated by Asian nations,
meaning that 64 million people in China would be affected by rising seas with a 2
degree rise in temperature. However, with a 4 degree rise this figure goes up to 145
million. China is followed in second place by India, with 20 million and 55 million
respectively. Whilst India’s neighbour, Bangladesh, completes the top three most at
risk, followed by Vietnam, Indonesia, Japan and the Philippines, which all appear in
the list. The only other nations to feature are the US, Egypt and Brazil at 7th, 9th and
10th respectively.
To this extent, ‘sustainable development’ in the built environment is essential, as it
aims to overcome the aforementioned puzzle, enabling humans to live healthier and
engage in a new, wiser era of industry. Therefore, it can be argued that
transformation of the world economy and society to a sustainable approach is the
most serious challenge of our time. However, this challenge is unprecedented in
context, as its scope is the entire planet. Consequently, it needs a radical shift in
consciousness as well as action. This indeed, requires new visions and meaningful
approaches for shaping ambitious realities.
23
2.3 Sustainable Development
Even though our earth is exquisitely configured to host life with abundance, humans
have systematically compromised almost every vital aspect of its complex systems. If
humans are to survive, this trend ought to be reoriented and a lasting balance
adopted. Ultimately, Sustainable Development (SD) aims to reflect such insight,
gaining increasing recognition in recent years worldwide. However, its widespread
use has led to a sense of ambiguous perception, since it is broadly employed with a
wide spectrum of understanding.
2.3.1 Definition of Sustainability
Sustainable Development (SD) is a simple word with a complex meaning. One report
indicates that SD is “one of the most widely used words in the scientific field” (Leal
Filho, 2000, p.9), yet it is deemed to be a complex term, deployed in different ways by
individuals, organisations, and governments, and thus, used to support a variety of
ambitions, and contested ends. Linguistically, the meaning of the verb ‘to sustain’
according to the Oxford English Dictionary is to keep something going over time or
continuously (Oxford, 1989). Whilst the term ‘sustainability’ refers to the avoidance
of the depletion of natural resources in development fields (Ben-Eli, 2015). It is
commonly acknowledged that SD originally derives from the concern that the global
consumption of resources and its production of waste could exceed the earth’s
capacity to produce these resources and absorb waste (Conard, 2013), reflecting the
object of a lasting ecosystem over time (Murray, 2011).
Ample definitions for SD have existed, hence it does not have a consensus for its
definition (Waas et al., 2011). While the classic definition of sustainable development
was introduced in the highly influential Brundtland Report from the World
Commission on Environment and Development (WCED), which provided the
prevalent definition for sustainable development:
“Development that meets the needs of the present without compromising the ability of future generations to meet their own needs” (WCED, 1987, p.8).
Arguably, the Brundtland definition was a political fudge as Leal Filho (2000)
asserted that it is based on an ambiguous meaning in order to gain widespread
acceptance. Others have argued that the vagueness of meaning makes the concept
almost meaningless and it lacks any clear rigour of analysis or theoretical framework
24
(Murray, 2011). However, Leal Filho (2000) pointed out that the basic idea of
sustainability is quite straightforward: a sustainable system is one which survives or
persists. Biologists and ecologists make use of the term to describe the rates at which
renewable resources could be extracted or damaged by pollution without threatening
the underlying integrity of an ecosystem (Ben-Eli, 2015). Meanwhile, Conard (2013)
described sustainability as individuals doing their part to build the kind of world that
they want to live in and that they want their children and grandchildren to inherit, so
that humans become aware of choices and behaviours that influence the intricate
balance of the earth’s social, ecological and economic systems. Recently, however, the
prevailing definition for sustainability focuses on cross-generational equity (Ben-Eli,
2015), which is undeniably a convincing concept.
“Sustainability is a dynamic equilibrium in the process of interaction between a population
and the carrying capacity of its environment such that the population develops to express its
full potential without producing irreversible, adverse effects on the carrying capacity of the
environment upon which it depends” (Ben-Eli, 2015, p.3).
Ben-Eli (2015) has asserted that grounding an alternative perception to the
interrelationship between a population and the carrying capacity of its environment
represents a revolutionary operational leverage. Furthermore, describing that the
current definition contains a range of key ingredients that are likely to be measurable,
for example, population size, resource use rate, absorption capacity of sinks, well-
being level, and the like. However, the current definition also presents difficulties, as
future generations’ claims seem undefined or undetermined. At the same time,
Murray (2011) concluded that there is agreement about what SD really indicates,
since it is fundamentally about the conservation of resources and the way by which
the next generations can share the current one with the benefits of development.
Interestingly, although the terms ‘Sustainability’ and ‘Sustainable Development’ are
often used interchangeably, there seems to be controversially functional differences
between the two concepts. According to Waas et al. (2011), while Sustainability
represents the ability to maintain a ‘desired condition’ over time, Sustainable
Development is considered as the tool required to achieve the desired goal
‘Sustainability’. Against this perception, Sustainable Development can be understood
as the path to amend unsustainability, whilst the basic premise of Sustainability
appears to be how sustaining the well-being of living systems can be achieved over
25
time (e.g. clear ethical values, guidelines for decisions or what priorities are).
Therefore, Sustainable Development needs to be based on norms that embed all the
issues that societies are concerned with (Waas et al., 2011). Given that this study
looks for an assessment model for sustainable homes, its nature revolves around the
concept of Sustainable Development, even though they are used interchangeably
through this thesis.
The main principles of Sustainability have been emphasised through a number of
initiatives, presenting and forming the concept of Sustainability in a broad set of
objectives and ambitions in order to facilitate delivering Sustainability in practices,
which is to be addressed within the next section.
2.3.2 The Main Principles of Sustainability
The ultimate goal of establishing Sustainability as a revolutionary concept is to
reinforce a well-functioning alignment between the economy, society and the planet’s
ecosystem. This alignment poses a range of mechanisms that ensure dynamic
equilibrium in the interaction between the components of Sustainable Development.
It is widely believed that the most prominent statement in this context, is the Rio
Declaration ‘Agenda 21’ at the Earth Summit of 1992. The United Nations Conference
on Environment and Development (UNCED) commenced the principles for
Sustainable Development with the agreement of more than 178 Governments
worldwide. The full Implementation of Agenda 21 and the Commitments to the Rio
principles, were strongly reaffirmed at the World Summit on Sustainable
Development (WSSD) held in Johannesburg, South Africa in 2002. More recently, a
distinguishing initiative has attempted to reflect a comprehensive set of Sustainability
principles. The 2030 Agenda for Sustainable Development was adopted by all United
Nations Member States in 2015. The recent agenda emphasizes a holistic approach to
achieving Sustainable Development for all, building on the principle of “leaving no
one behind” (SDGs, 2015). ‘Envision2030’ promotes the mainstreaming of the
establishment of Sustainability throughout its 15-year lifespan with 17 key principles
to transform the world (SDGs). Table 2.1 shows the 17 key Sustainable Development
Goals (SDGs, 2015).
26
Table 2.1: The 17 key Sustainable Development Goals
A review of the principles implies that an attempt to implement a transition to
Sustainability, which is a piecemeal framework focusing on selective aspects while
omitting some others, is unlikely to pose successful, lasting outcomes. Consequently, a
systemic approach is fundamental. As it reacts with the interdependent nature of
reality itself. Therefore, it is of utmost importance to comprehensively incorporate the
key Sustainability principles into any attempt at building a rigorous framework for
implementation, so that it is intended to meet a range of these principles through the
proposed model and this will be reflected in the discussion of the potential findings of
this study.
27
2.4 Sustainability in Construction
It is widely accepted that the construction sector can significantly reinforce the
achievement of Sustainable Development; and its role in encouraging environmental
protection, economic growth and social progress is undeniable (Heravi et al., 2015;
Fenner & Ryce, 2008; Kibert, 2008; Edwards, 2000). The abundant definitions of this
concept and the main principles of sustainable housing building are to be highlighted
before addressing the underlying impacts of construction activities through the
following sub-sections.
2.4.1 The Broadness of Sense
The term of Sustainable Construction (SC) appeared approximately at the same time
as the evolution of the concept of Sustainable Development (SD), referring to
comprehensive solutions for ecological, social and economic issues (Kibert, 2008).
Reviewing the relevant literature reveals that there are tremendous initiatives that
aim at conceptualising the concept of Sustainability in the built environment domain
including concepts such as Sustainable Construction, Sustainable Building, Sustainable
Architecture, and Sustainable Communities. However, the first initiative amongst
them, was presented in 1994, by the ‘Conseil International du Batiment’ (CIB)1 as an
overarching understanding aimed at conceptualising Sustainable Construction (SC) in
a broad domain:
“… creating and operating a healthy built environment based on resource efficiency and ecological design” (Kibert, 2008, p.10).
In the same context, according to Glavinich (2008) the term green building was
defined in the American Society of Testing and Materials (ASTM) as a building that
provides the specified building performance requirements while minimising
disturbance to and improving the functioning of; local, regional and global ecosystems
both during and after its construction and specified service life. Meanwhile, Fenner
and Ryce (2008) presented a comprehensive vision for green building as follows:
“Green buildings may be considered as structures that incorporate environmentally sensitive features and technologies from the initial design phase; they seek to meet or exceed resource and energy consumption targets that are set well above local requirements while taking into account the whole life cycle impact of the structure” (Fenner & Ryce, 2008, p.55).
1 CIB is the acronym of the abbreviated French name; the abbreviation has been kept but the full name changed into: International Council for Research and Innovation in Building and Construction.
28
Similarly, Sustainable Building is a concept which reflects incorporation of the
principles of Sustainability with the aim of minimising the impact of building projects
on the natural environment, as Godfaurd et al. (2005) stated:
"… those buildings that have minimum adverse impacts on the built and natural environment, in terms of the buildings themselves, their immediate surroundings and the
broader regional and global settings” (Godfaurd et al., 2005, p.320).
Accordingly, Sustainable Architecture can be defined as design which meets human
demand whilst having a minimalistic impact on the natural environment (Edwards,
2000). This implies that Sustainable Architecture is mainly concerned with
ecologically internal and external buildings. Thus, there seems to be extensive
evidence to assert the importance of the role of building projects as a starting point for
achieving Sustainable Communities. As Edwards (2000) stressed that sustainable
communities can be shown as one of the ultimate goals, which allows people to spend
long periods of time in their neighbourhood:
"Living in harmony with the environment has become an essential component of the design of homes and neighbourhoods in the third millennium" (Edwards, 2000, p.7).
Despite the prevalent use of such a range of concepts, truly Sustainable Construction
with efficient energy systems, recyclable materials, and full-integrating ecosystems
are rare to nonexistent. The reverse impacts of construction activities are apparently
shown through a wide range of aspects including raw material consumption, pollution
and waste generation, energy use, and health and wellbeing. These issues are
discussed in the following section.
2.4.2 Construction Impacts on the Environment
The construction industry is among the most resource-intensive industries
worldwide. Therefore, the impacts of construction activities on both humans and the
ecosystems is increasingly concerning. Evidently, action is urgently needed to
incorporate Sustainability into built environment and building performance (Abidin,
2010; Ding, 2008; Cole, 1998). As the environment and construction activities seem
to be closely linked, the building community is deemed as the centric focus in relation
to environmental problems (Jain, 2013). Moreover, Abidin (2010) reported the
building sector as one of the major contributors to environmental degradation.
Whilst, the building community has been classified by a range of scholars (Ding, 2008;
Cole, 1998) as apparently demonstrating a careless manner, being financially
29
revenue-motivated, and ultimately portrayed as environmental destroyers instead of
protectors. It is undeniable that the impacts of the construction industry to a large
extent are irreversible for the surrounding environment, and the ecosystems which
act throughout the project life cycle (Ding, 2008). Figure 2.8 illustrates the various
stages of a life cycle in a building project, including the harvest of raw materials and
production of components in alignment with the stages of planning, design,
construction, operation and deconstruction phases.
Figure 2.7: Environmental Impact through the Life Cycle of a Building Project (Source: Jain, 2013).
Arguably, although it has a substantial effect on the environment, the period of the
construction phases is relatively short amongst the entire project lifecycle. As such,
the environmental impacts of the building projects are to be analysed in a manner
that ensures accommodating the whole life cycle of a building.
2.5 Shift to Sustainable Homes
Homes not only offer accommodation, but also grant a sense of security while
strengthening local communities. Firstly, the concept of home and its perspectives are
to be highlighted before addressing the features required for a successful shift to sus-
tainable homes through the following sub-sections.
30
2.5.1 The Concept of Home
The concept of home has many origins and can be seen from different perspectives.
People live in a world of symbols created by themselves, that express their percep-
tions and intentions in a way that is reflected through a range of objects. Home as a
concept is a fundamental notion in people’s minds, and for many, has a powerful
symbolic charge, as indicated by Lantz (1996). Interestingly, ‘home’ and ‘house’ as
terms, are very often used interchangeably. The Oxford dictionary defines the terms
home and house as synonymous, referring to a building where someone lives (Oxford,
1989), although linguists would probably differentiate between them.
The main difference is that a house is concrete or has a physical location, whilst a
home can even be something abstract, such as a place in the mind or any location that
people think of as the place where they live and that belongs to them. “Home is where
the heart is” is a well-known expression, that truly indicates home as somewhere that
is both desirable and that exists in the mind, as much as in a specific physical struc-
ture. However, reviewing the body of literature (Cooper, 2003; Roaf et al., 2003;
From another perspective, a number of studies have been conducted in various local
regions worldwide, aiming to develop assessment models by incorporating
Sustainability features in building projects. For example, Ali and Al Nsairat (2009)
developed a green building assessment model (SABA Green Building Rating System)
for the Jordanian context. With the SABA model assessing water efficiency as top
amongst the seven features identified, with 27.7%. Whilst the rest scored as follows:
energy efficiency (23.0%); indoor environmental quality (11.8%); site selection
(10.3%); materials and resources (10.3%); economics (10.0%); and waste and
pollution (6.4%). In addition, a study by Mateus and Bragança (2011) involved a
model for Sustainable Development for residential buildings (SBToolPT) in urban
areas, especially suitable for Portuguese standards, society and climate. The
SBToolPT model encompasses nine sustainability domains, namely; energy efficiency;
water efficiency; land use and biodiversity; materials and waste management;
occupant’s health and comfort; accessibilities; climate change and outdoor air quality;
education and awareness of Sustainability; and life-cycle costs. While, a
Comprehensive Assessment System for Sustainable Housing (CASSH) was conceived
to evaluate sustainable housing in regard to Malaysian tradition and was conducted
by Bakar and Cheen (2011). The CASSH system consisted of three major levels; the
outcome, design measurement indicators, and sustainability criteria level. It sought to
reflect sustainable housing either under construction, new development or
refurbishment. From economic perspective, Mulliner et al. (2013) used the COPRAS
method in Liverpool to evaluate sustainable housing affordability in the UK context.
This study compared three different residential areas in accordance with a set of 20
weighted criteria. The results showed that compared with the use of only one
economic-based approach, its recognition to environmental and social criteria
46
significantly affected the calculation of affordability for a specific area. Similarly,
Sourani’s (2008) study aimed to develop a framework to aid UK public clients in
incorporating sustainability interventions in construction projects' procurement
strategies. This included a set of 17 social sustainability criteria, 12 economic
sustainability criteria, and 13 environmental sustainability criteria. A further study in
Sri Lanka conducted by Chandratilake and Dias (2013) established a rating system
that encompassed weighting criteria using six domains (site, energy efficiency, water
efficiency, materials, indoor environmental quality, waste and pollution) in the
national context. Alyami et al. (2013) in turn, presented a Saudi Environmental
Assessment Model. The SEAM scheme comprised of a list of 92 indicators for
assessing sustainable residential buildings, divided into ten major categories (site
quality; energy efficiency; indoor environmental quality; water efficiency; pollution;
waste management material; quality of services; economic features; cultural features;
and management and Innovation).
Accordingly, based on a comprehensive study on the UK social housing, Higham and
Stephenson (2014) suggested a set of 49 project success criteria, grouped into six
principle areas (Built Environment, Local Environment, Market Dynamics, Local
Economy, Society, and Governance). In contrast to the Chinese built environment,
where Yu et al. (2015) presented an assessment tool for green store buildings, that
included seven major categories (landscape, water efficiency, energy efficiency,
indoor environment, material and resources, operation management and
construction management). Burdova and Vilcekova (2015) in turn, presented a
Building Environmental Assessment System (BEAS) which was developed in the
Slovak Republic, it encompassed a large range of environmental, economic and social
indicators that represented the Slovak standards and rules. While, more recently,
Mardani et al. (2016) presented a hierarchical framework for assessing and ranking
the significant factors of energy-saving technologies and solutions in the ten biggest
Iranian hotels. Finally, a study by Abdul-Rahman et al. (2016) presented a ranking
sustainability model of Fuzzy Weighted Hierarchy for Triquetrous Sustainability
(FWH-TS), which integrated various environmental, economic and social indicators
and criteria for housing. Ultimately, a review of the aforementioned initiatives has
revealed that although many authors have developed a wide range of national
47
sustainability assessment systems, there is no agreement on the nature and extent of
the indicators to be measured. As Higham et al. (2016, p.156) state:
“There exist significant conflicts between the models proposed regarding their detail, the measurement and evaluation approach, and the nature of their overarching features, so a suitable structured framework to assist project teams involved in the delivery of sustainable building projects is lacking”.
It is also clearly notable that relatively little has been written on sustainability
assessment methods for the built environment in the context of developing countries
(Ali & Al Nsairat, 2009; Chang et al., 2007) and even fewer have examined the
characteristics distinguished for the Libyan built environment (Elgadi et al., 2016;
Shawesh, 2016; Shibani & Gherbal, 2016). This study, therefore, is built on the claim
that it is essential to develop an applicable sustainability-based assessment model to
effectively deliver sustainable homes in the Libyan building sector.
2.7 Chapter Summary
Through the development of people’s living standards and the industrial revolution,
population growth has increased, and natural resource depletion has reached
detrimental levels, which have led to negative effects on the natural environment
such as global warming and climate change. Consequently, this situation requires new
visions and meaningful approaches that collectively consider multi-dimensional
development. Yet, Sustainability is widely varied in terms of its definition, there is
consensus that it should engage with three key dimensions, namely: environmental,
social and economic. Sustainability in the construction field, and particularly homes,
reflects better performance when it ensures the incorporation of issues such as
It can be noted that all the tools classified in the ATHENA classification belong to the
second or third category in the IEA Annex 31 classification, and there is a broader field of
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classified systems within the IEA Annex 31 classification than in ATHENA. The ATHENA
classification, as Trusty (2000) asserts, depends on the location and purpose of use of
assessment processes, while the IEA Annex 31 encompasses energy modelling software,
various environmental standards and guidelines, checklists, product declarations and
certifications. In addition, the IEA Annex 31 (2017) differentiates between interactive
software and passive tools as the former relies more on information technology. However,
ATHENA classification level 1 and 2 tools depend more on information technology than
those of level 3. In the ATHENA classification, level 1 tools are used mostly for product
comparison while level 2 and 3 tools are utilised for the environmental assessment of a
whole building.
However, for comparison to be more effective, Trusty (2000) states that, the contrast
should be within the classification level. For instance, in the ATHENA classification, Level 1
tools should only be compared with other Level 1 tools and not with those of Level 2 or 3.
In this way, it is possible to evaluate and compare inter-level differences, uncover any
weaknesses and allow for future development. Thus, the study is interesting in the
development of ATHENA level 3 which corresponds with the third class in the IEA Annex
31 model, building sustainability assessment frameworks and rating systems.
4.2.3 Rating Systems
Given the fact that not every criterion can be seen as equally important, the weighting
method is considered the heart of any SAM scheme (Ding, 2008; Chew & Das, 2008; Cole,
2005). A weighting system comprises a means to manage perspectives for credit
distribution (Cole, 2005). The weighting system often includes a calculation procedure
(weighting coefficient, rating formula and benchmarking expression), providing a single
result indicating a clear level of sustainability achieved. The SAM systems employ various
strategies for assessment, for instance, the BREEAM employs a weighted system that
prioritises sustainability criteria, while LEED uses a simple additive method (1 for 1) in
which all criteria are weighted equally. However, making an assessment without a
weighting system inevitably leads to criticism, because it is still the only approach proven
to comprehensively evaluate and prioritise complex issues relating to sustainable
development (Lee, 2013). Therefore, when intending to develop a new SAM, it is
appropriate to offer a customised weighting system to meet local and regional priorities,
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ensuring that the study will develop its own rating system that will structure a reliable
assessment tool for sustainable homes in the context of Libya.
4.3 Overview of the Prevailing SAMs
Extensive schemes of SAM have been presented in different countries around the world.
These assessment systems have been developed initially on the basis of specific conditions
so as to be applicable to the characteristics of the regions for which these systems are
designed. For example, in the UK, there is the Building Research Establishment Assessment
Method (BREEAM), in the USA the Leadership in Energy and Environmental Design (LEED),
the Green Building Council Australia (GBCA) in Austria, there is the German sustainable
building certificate (DGNB), and the Comprehensive Assessment System for Built
Environment Efficiency (CASBEE) in Japan. In addition, there are extensive models that are
based on Life Cycle Analyses, for instance, EcoQuantum in Netherlands, EcoEffect in
Sweden, Environmental impact analysis for buildings ENVEST in the UK, Building for
Environmental and Economic Sustainability (BEES) in the USA, Athena Sustainable
Materials Institute Life Cycle Assessment (ATHENA) in Canada, and Life Cycle Assessment
(LCA) in Finland. A range of the most widely used SAMs adopted in various nations is
encapsulated in Table 4.1 below.
Table 4.1: The Various SAMs Around the World
No Tool name Country Year No Tool name Country Year 1 BREEAM UK 1990 2 PassivHaus Germany 1991 3 Austin Green Building Program US 1992 4 BEPAC Canada 1993 5 Colorado Built Green Housing US 1995 6 HK-BEAM Hong Kong 1996 7 HQE France 1996 8 LEED US 1998 9 GBTool International 1998 10 EEWH Taiwan 1999
11 EarthCraft House US 1999 12 DDC US 1999 13 SDS Australia 1999 14 HQAL Japan 2001 15 Built Green Alberta US 2001 16 BEAT Denmark 2001 17 FGBC Florida, US 2002 18 ARE Scorecard Australia 2003 19 GEM UK 2003 20 Go Green Canada 2004 21 Green Globes US 2004 22 ProtocolloItaca Italy 2004 23 BASIX Australia 2004 24 Docklands ESD Guide Australia 2005 25 Green Mark Singapore 2005 26 Green Communities US 2005 27 NAHB US 2005 28 LiderA Portugal 2005 29 EnviroDevelopment Australia 2006 30 Code for Sustainable Homes UK 2006 31 AccuRATE Australia 2007 32 Minnesota GreenStar US 2007 33 BEES US 2007 34 Living Building Challenge US 2007 35 Green Star NZ New Zealand 2007 36 LEED-Brazil Brazil 2008 37 First Rate Australia 2008 38 GOBAS China 2008 39 Green Star SA Africa 2008 40 DGNB Germany 2008 41 LEED- India India 2008 42 Green Building Index Malaysia 2009
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4.4 Justification of an Integrated Analysis of the Four SAMs Selected
It is widely acknowledged that when developing a new Sustainable Assessment Method
(SAM) to begin with an integrated analysis of reliable methods is required (Sleeuw, 2011;
Poston et al., 2010; Cole, 2005). In following up this orientation, this research aims to
develop a theoretical framework through conducting an integrated analysis of a range of
well-established and globally recognised SAMs. As aforementioned, this study targeted four
common methods in use, namely “The Building Research Establishment Assessment
Method” (BREEAM); “Leadership in Energy and Environmental Design” (LEED); “German
sustainable building certificate” (DGNB); and “Green Building Council Australia” (GBCA),
and then compared their parameters in order to aggregate the key categories and criteria,
thereby establishing the proposed framework of the research. A wide range of national
SAMs worldwide (see Table 4.1 above) have been established on the basis of well-known
schemes such as BREEAM and LEED so that the focus was initially oriented towards the
well-established tools rather than those were generated on the basis of which.
For this study, the adoption of the four models in this study have been driven by the basis
of many motivating considerations. The selection of these well-known models is initially
dependent on the credibility and reputation of the institutions that launched and operated
them as well as their success in the marketplace. Globally, BREEAM and LEED are the
leading methods in relation to building assessment methods, operated by well-known
institutions (i.e. BRE and USGBC) that have a significant record in their domain. A case in
point, 560,000 buildings have been assessed and certified by BREEAM, with roughly 2.25
million projects registered for certification cross 76 countries (BREEAM, 2018). Similarly,
the USGBC have calculated that the number of projects certified and registered under LEED
reached around 90,000 by the end of 2018, covering 165 countries (LEED, 2018).
The final two methods are selected for slightly different reasons. GBCA and DGNB were
chosen because of their comprehensive nature since they more closely consider issues
related to economic and social dimensions. They are also widely considered the most
comprehensive methods of sustainability in the building sector (Tupenaite et al., 2017;
Markelj et al., 2014; Ebert et al., 2011; Khezri, 2011; Poston et al., 2010). In addition, GBCA
has been chosen because it was originally established in Australia with differences in
environmental characteristics - particularly the climate - allowing for more diversity and
enriching the comparison planned.
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4.5 Models Comparison Overviews
Methods such as BREEAM and LEED have attracted the attention of researchers as they
provide rigorous development systems (Tupenaite et al., 2017; Markelj et al., 2014; Sleeuw,
2011). This chapter presents a comparison of the four various Sustainability Assessment
Methods (SAMs) (BREEAM, LEED, GBCA, DGNB) established in different regions over the
world (the UK, USA, Australia, Germany). See Appendices 1. 2, 3 and 4 for more details.
4.5.1 BREEAM
BREEAM is the world’s leading SAM for master planning projects, infrastructure and
buildings. It recognises and reflects the value in higher performing assets across the built
environment lifecycle, from new construction to in-use and refurbishment (BREEAM,
2018). In 1990, BREEAM initiated and began functioning through BRE which is an
independent institution that has a long history of about 100 years for testing and training
and it is mainly known as a consulting organization that provides experience and
consultations in all parts of the built environment as well as the linked industries. The
scope of BREEAM covers various types of schemes including BREEAM Buildings (i.e. New
Construction; Refurbishment and Fit Out), BREEAM Communities, and BREEAM
Infrastructure New Construction (BREEAM, 2018). In recent years, BREEAM schemes have
been developed and operated by National Scheme Operators (NSOs) in accordance with the
Code for a Sustainable Built Environment. This resulted in launching the “Code for
Sustainable Homes” (CSH) in 2007 as a sustainability assessment method for rating and
certifying the performance of new homes. CSH currently represents a national standard for
use in the design and construction of new homes with a view to enhancing continuous
improvement in sustainable homes (BREEAM, 2018). BRE act as advisors on technical
standards in relation to development and maintenance and manage implementation of the
system through evaluation and certification services, under contract to the “Department of
Communities and Local Government” (DCLG). Recently, the 2017 version of the BREEAM
has been linked with the International WELL Building Institute (IWBI), which is expected
to make it easier for projects pursuing both standards (BRE, 2018). Moreover, all BREEAM
activities are formally documented and certified by ‘International Organisation for
Standardization’ ISO 9001 which has offered a set of sustainability-based requirements for
building assessment (BRE, 2016).
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Credits and Percentage Points
The latest version of BREEAM “Code for Sustainable Homes” (CSH) was in 2010, and it
consists of 34 individual assessment issues, separated into nine categories (i.e. Energy and
CO2 emissions, Water, Materials, Surface Water Run-off. Waste, Pollution, Health and
Wellbeing, Management, and Ecology), each addressing a specific home related
sustainability impact, as shown in Figure 4.1 below.
Figure 4.1: BREEAM’s categories “The Code for Sustainable Homes” (Adapted from BRE, 2010)
Rating System
The issues identified in CSH are employed to assess a performance target of the intended
project and each criterion can be awarded numbers of credits. The weighting factors show
the contribution made by each category to the total performance recognised and rewarded
by the Code. This establishes the Code level or rating for the housing project. The Code
certificate illustrates the rating achieved with a row of stars where a blue star is awarded
for each level achieved and the total available score is expressed as 100 per cent. The
aggregated credits in BREEAM produce an ultimate single score as follows: one star (36-
47); two stars (48-56 points); three stars (57-67 points); four stares (68-83 points); five
stars (84-89 points); and six stars (90-100 points) (BRE, 2010). Figure 4.2 below shows the
six levels of BREEAM’s rating system.
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Figure 4.2: BREEAM’s rating system “The Code for Sustainable Homes” (Adapted from BRE, 2010)
4.5.2 LEED
LEED is a voluntary certification program developed by the “U.S. Green Building Council”
(USGBC), providing an inclusive assessment method (LEED, 2018). LEED was launched in
1998, known as the LEED 1.0 version which actually was influenced by BREEAM
approaches (Sleeuw, 2011). LEED v4 is the most resect version of LEED, designed to be
flexible and improve the overall project experience. LEED covers various types of building
project, including BD+C (Building Design and Construction), ID+C (Interior Design and
Construction), O+M (Building Operations and Maintenance), ND (Neighbourhood
Development), and Homes (LEED, 2018).
Credits and Percentage Points
LEED for homes design and construction grants a maximum of 110 credits through 61
criteria split up into nine categories. These categories assess a broad range of features
related to sustainability in housing projects, including Location and Transportation,
Sustainable Sites, Water efficiency, Energy and Atmosphere, Materials and Resources,
Indoor Environment Quality, Innovation, Regional Priority, and Integrative Process. Each
aspect is assigned with numbers of credits which are awarded based on the performance
targets. The total available credits are 110 points. Figure 4.3 visualises the credit systems
adopted in LEED for homes and for facilitating the comparison, percentage points were
estimated.
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Figure 4.3: LEED’ Categories “Homes Design and Construction (v4)” (Adapted from: USGBC, 2013b)
Rating System
For calculating the achieved credits, LEED, unlike BREEAM, adopts a simple additive
approach (1 for 1) with all criteria being weighted equally, rather than using a weighting
system. LEED promotes four different ratings: certified (40-49 points); silver (50-59
points); gold (60-79 points); and platinum (≥80 points) (USGBC, 2013a), as shown in
Figure 4.4 below.
Figure 4.4: LEED’s Rating System for Homes Design and Construction (v4). (Source: LEED, 2018)
4.5.3 GBCA
Green Building Council Australia (GBCA) or well-known as ‘Green Star’ is an Australian
rating system, developed by the Green Building Council Australia in 2003 (GBCA, 2018).
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GBCA was designed based on various SAMs such as BREEAM and LEED (Roderick et al.,
2009) and was originally developed to accommodate buildings’ requirements in hot
climates, where issues such as solar shading and cooling systems are of considerable
significance (Roderick et al., 2009). GBCA produced this method to comprehensively
facilitate delivering the requirements of the environment and people in their buildings
through different purposes: to minimise the impact of buildings on the environment
(environmental perspective); to reinforce the health and productivity of the buildings’
users (social/user perspective); and to achieve cost savings (economic/financial
perspective) (GBCA, 2018). There are four GBCA schemes available for certification: (i)
performance; (ii) design and as built; (iii) interiors; and, (iv) communities. The latest
version of these models is ‘GBCA – Design and As Built v1.2’. This was released in 2017 to
assess the sustainability outcomes from the design and construction of new buildings or
major refurbishments across nine holistic impact categories (GBCA, 2018).
Credits and Percentage Points
The ‘GBCA Design and As Built v1.2’ encompasses a set of 67 criteria, which are grouped
into nine categories, namely Management, Indoor Environment Quality, Energy, Transport,
Water, Materials, Land Use and Ecology, Emission, and Innovation. Each cluster is a source
of sustainability impact which is supposed to be assessed against a desired performance
and awarded credits. The ‘GBCA Design and As Built v1.2’ presents 91 points in total.
Figure 4.5 illustrates the credit systems adopted in GBCA, whilst percentage points were
generated to facilitate the intended comparison.
Figure 4.5: GBCA’s Categories “Design & As Built v1.2”. (Adapted from GBCA, 2018)
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Rating System
The total number of points achieved through the process of assessment in the ‘GBCA
Design and As Built v1.2’ can be compared against the available points in the rating tool
which describes the sustainability attributes of the project on the basis of 1-3 Stars (10–44
points), 4 Stars (45–59), 5 Stars (60–74 points), and 6 Stars (≥75) (GBCA, 2018), as shown
in Figure 4.6 below.
Figure 4.6: GBCA’s rating system “Design & As Built v1.2”. (Source: GBCA, 2018)
4.5.4 DGNB
‘German sustainable building certificate’ (DGNB2) is the first German method for assessing
and planning buildings in reference to sustainable building principles (DGNB, 2018a). The
basic system for assessing the sustainability quality of buildings was jointly developed by
the DGNB and the “Federal Ministry of Transport, Building and Urban Development”
(BMVBS) in 2009. While the BMVBS has precisely specified this basis for the self-
assessment of federal buildings, the DGNB has developed a complete certification system
for a wide range of building uses and quarters (Ebert et al., 2011). The DGNB was designed
for different types of buildings, including existing buildings, new buildings, inside rooms,
and quarters. DGNB currently is one of the leading SAMs worldwide, representing the
certification systems of the second generation as a result of its comprehensive
consideration that takes equal account of environmental, economic and social aspects as
well as its holistic view of the building’s entire life cycle (Khezri, 2011; Ebert et al., 2011).
2 (DGNB) Deutsche Gesellschaft für Nachhaltiges Bauen
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Credits and Percentage Points
The sustainability concept of the DGNB system is broad and extends beyond the well-
known three-pillar model. It considers all essential aspects of sustainable construction,
including the six subject areas of ecology, economy, socio-cultural and functional aspects,
technology, processes and location which in turn, are split down into 151 criteria. Each
single criterion can receive a maximum of 10 points and has its own weighting rate, but it is
possible to increase this rate depending on certain features (DGNB, 2018b). Likewise, the
six categories have their own credits as well as the weighting factors, as shown in Figure
quantitative and qualitative research have their problematic issues which most often result
in biases, so that a combination of different methodological perspectives in one inquiry
paradigm is critical to overcome the weaknesses in each approach while enhancing the
validity of the overall output of a research study. The pragmatist researchers are willing to
carry out a variety of approaches for collecting and analysing different evidence rather
than sticking merely to a single methodological stance (Mertens, 2009). In relation to this,
Creswell (2013a) asserts that researchers should choose their approaches depending on
determinants such as the nature of research questions, researcher experience, and the
audience. The next sub-sections highlight in detail the main distinguishing attributes of
qualitative, quantitative and mixed method methodology.
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5.5.1 Qualitative Methodology
Qualitative research is more likely to perceive human experience and knowledge since it is
typically associated with social and cultural investigations. Creswell (2013b) describes
qualitative research as ‘an inductive, interpretive, and naturalistic approach’ to the study of
people, cases, phenomena, social situations, and processes in their natural settings in order
to reveal the perceptions that people consider regarding the phenomenon being
researched. Qualitative research employs a relatively small sample size of participants and
relies on words as data, rather than numbers (Braun & Clarke, 2013). With an adequate
number of participants, qualitative research tends to produce narrow but rich data, with
detailed descriptions and complex narratives from participants (Braun & Clarke, 2013),
capturing facets of social reality while considering and examining differences within data
so as to understand and interpret the essence of a phenomenon (Braun & Clarke, 2013).
Qualitative research, as Creswell (2013b) indicates, can benefit researchers to gain a deep
insight into complexities. Qualitative data is collected via means such as open-ended
surveys, interviews, focus groups, observations, or ethnographies (Creswell, 2013b).
Qualitative methodology basically, as Braun and Clarke (2013) explain, has two principle
distinctions which are: (i) inductive, this is because the research starts from the specific
and ends with a general phase which means a down-up approach, so it is used to develop
theories; and, (ii) subjective, this can be traced back to researchers’ value interference
throughout the research process.
Qualitative methodology has some distinct strengths as Creswell (2013b) indicates. A
qualitative approach offers the option of selecting a small sample size to deeply focus on,
considering participants’ perceptions as the main source of data. A qualitative approach is
ideal for carrying out research of complex phenomena because it provides more detailed
descriptions of individuals’ experiences. However, the qualitative methodology has its own
weaknesses. It may not be sufficiently rigorous, lacking in validity and reliability, and it is
unlikely its findings will be applied in a systematic, consistent manner (Creswell, 2013b).
The generalisability of results, as Bryman (2015) indicates, is also an issue, seen as a
weakness that affects the findings of qualitative research.
5.5.2 Quantitative Methodology
Quantitative research is typically associated with the natural sciences that are intended to
investigate natural phenomena. This form of research involves the explanation of a social
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science phenomenon using mathematical based approaches. As Creswell (2013a)
demonstrates, quantitative methodology is a type of empirical research into a social
phenomenon or human issues through the testing of theories consisting of variables which
are measured with numbers and analysed with statistics in order to determine whether or
not the theory explains or predicts the phenomenon. It often seeks to examine
relationships between variables in order to interpret or predict a phenomenon (Bryman,
2015). The quantitative data collected is often broader than qualitative, but has less depth
(Creswell, 2013b). Therefore, quantitative research is unlikely to collect complex detailed
data. Rather, quantitative research simplifies the diversity of responses in order to
establish a generalisation of the findings (Saunders et al., 2016). Quantitative research is
attributed with two characteristics, which are: (i) deductive, this means that it is used to
test theories because it starts from general and ends with specific level or up-down
approach; and, (ii) objective, this means it detaches the researcher from the researched
(Braun & Clarke, 2013).
In a social science domain, the most common quantitative method used is the survey
technique. The advantage of adopting a quantitative survey approach is that it employs a
large sample which is more representative (Creswell, 2013b). Data collected can also be
statistically analysed via advanced software (Creswell, 2013b). A quantitative approach
offers a clearer summary of key components of findings that are applicable for re-
researching by other researchers (Braun & Clarke, 2013). However, there are also
weaknesses affecting quantitative methods since they require the participants’
perspectives to fit into pre-determined response categories (Braun & Clarke, 2013). As
Bryman (2015) indicates, employing such methods for examining social reality might not
reflect the genuine realities of the participants. Creswell (2013a) also notes that
quantitative research usually misses out participants’ perceptions and understandings
from the collected data, confirming that statistical samples in quantitative methods are
unlikely to represent particular social groups or individuals’ perceptions.
5.5.3 Mixed Methodology
A mixed approach is a sort of research that allows researchers to combine both qualitative
and quantitative methods. As Tashakkori and Creswell (2007) identify, a mixed
methodology is:
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“research in which the investigator collects and analyses data, integrates the findings, and draws inferences using both qualitative and quantitative approaches and methods in a single study or program of inquiry” Tashakkori and Creswell (2007, p.12).
Mixed methodology employs inductive and deductive or also known as an abductive
approach (Creswell & Clark, 2011). Thus, mixed approaches benefit from two types of
evidence, qualitative data which is extracted directly from the participants’ perceptions
and provides rich descriptive details, whilst quantitative data which enhance objectivity
and generalizations as numerical are derived from an extensive sample size (Cohen et al.,
2013). Mixed approaches, as Creswell and Plano Clark (2011) advocate, pay greater
attention to the actions and consequences of the research, and its primary focus is on the
research question rather than the method itself.
It is agreed that there are considerable advantages to using a mixed approach. The use of
mixed methodology can minimise the weaknesses of the two quantitative and qualitative
approaches (Creswell & Clark, 2011). Offering researchers the flexibility and ability to be
integrative (Maxwell, 2008), mixed methodology can address both sets of questions,
providing the depth of qualitative understanding and the breadth of quantitative
techniques which strengthens the data collection and reinforces the findings (Cohen et al.,
2013). Moreover, this approach is useful when either the quantitative or the qualitative
approach alone would not be adequate for addressing the research questions. Another
advantageous point, as highlighted by Creswell and Clark (2011), is that the findings of a
mixed approach are generalizable.
In light of this, it can be argued that the broad spectrum of methodological philosophy and
instruments makes it more flexible for a researcher to adopt the most relevant approach to
the nature of enquiry. For this study, as mentioned earlier, a mixed methodology approach
is adopted to fulfil the aim of study. Further justification for this decision is provided in the
section that follows.
5.5.4 Methodological Approach Adopted and Justification
The theoretical model of this study addressed within the previous chapter together with
the research objectives have explained the main features of the methodological approach
that should be employed. Initially, the principle purpose of this study is to provide a
decision support system to promote sustainable development in the Libyan housing
projects. This stems from the central aim of the study, namely: “To customise an applicable
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composite index for assessing Libya’s sustainable homes”. To respond to this aim, it is
appropriate to set the concept of sustainable homes as a normative model determining the
relevant criteria that enables the assessment of their characteristics against the potential
performance. The exhaustive review of existing literature revealed no robust research has
been conducted to date to investigate the key sustainability indicators for housing projects
in Libya (Elgadi et al., 2016; Shibani & Gherbal, 2016; Almansuri et al., 2009).
Consequently, it was determined that the research would have to initially provide an
inductive exploration of the meaning of sustainability within the Libyan context, and
specifically the factors likely to influence sustainable design and construction. In line with
this, the concept of sustainability, as defined by Waas et al. (2011), is:
“Sustainable Development implies societal and normative choices, which are ultimately based on the values we maintain” (Waas et al., 2011, p.9).
This makes it difficult to derive a set of sustainability-based criteria purely from the
concept of sustainability with a deductive approach. Sustainability is evidently a poorly
defined, complex, and vague construct, which, as Braun and Clark (2013) state, requires a
deep investigation through qualitative data underpinned by interpretivist assumptions.
Therefore, a deep discussion and rigorous understanding about what future homes
demand to meet the sustainability requirements is needed. However, a purely qualitative
research design would present some limitations for the attainment of this aim. For
example, difficulties in applying it (i.e. access or interpretation), data analysis, and
generalisation of findings (Creswell, 2013b), whilst qualitative research would also present
distinct strengths such as being more interactive, as researchers structure the meaning
from the participants’ experience and knowledge, applying an adequate sample in depth,
flexibility, and convenience (Bryman, 2015). Thus, an inductive approach that allows
reflection and discussion is an important approach for satisfying a part of the inquiry in
this study.
On the other hand, the nature of the research seeks to justify a set of criteria to develop an
assessment model, and this epistemologically demands a sense of objectivity in its process,
requiring a quantitative method underpinned with an objectivist stance and statistical
techniques for data collection and results. As Cohen et al. (2013) advocate, a quantitative
approach presents quantitative evidence, enhancing the objectivity and generalisation. As a
result, mixed approaches through an abductive approach extending across the boundary
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between qualitative and quantitative approaches is inevitably needed to efficiently respond
to the questions identified through the study in hand.
In using such an approach, a researcher can use a variety of combinations of mixing the
methods to carry out research depending on the timing, integration level and priority given
to the quantitative or qualitative aspect of the research (Creswell & Plano Clark, 2011). In
this sense, the mixed methods approach, according to Bryman (2015), can be conducted
using four key techniques: (i) triangulation, which is used in parallel quantitative and
qualitative approaches; (ii) exploratory, which involves sequential use with qualitative
proceedings; (iii) explanatory, involving sequential use in reverse order; and, (iv)
embedding one type of method to supplement other techniques. Amongst various
combinations, for this study, exploratory sequential mixed methods approach is considered
the most appropriate approach because it mainly gives the priority to an interpretivist
stance with the inductive process as a predominant method. Starting with qualitative
evidence can help to get in-depth data regarding the crucial determinants influencing
sustainability in housing investments, then moving on to the positivist stage with a
deductive process and quantitative evidence to build up a solid worldview by which the
researcher gains insights into the phenomenon of interest. Even though the two stages are
separate, they are connected later through the data interpretation and discussion. Hence,
this methodological design, as advocated by Creswell and Clark (2011) and Morgan (2007),
is distinguished as being easy to apply and preferable to non-experienced researchers.
Against the understanding of Saunders et al.’s (2016) onion, together with the
methodological considerations defined for this research and described earlier, it can be
concluded that the pragmatic paradigm is consistent with the purpose of the study.
Consequently, a mixed methods approach adopting an abductive two-phase process with a
qualitative inductive process at the outset followed by a quantitative approach to rank and
sort the emergent variables whilst ensuring generalisability, is the methodological decision
that is considered appropriate for this study. This can be traced back to the nature of the
subject area of the study which is concerned with sustainability in housing investments as
a poorly defined phenomenon characterised by uncertainty and complexity and needing an
exploratory stance via an inductive process with qualitative method. Developing an
assessment model for sustainable homes in Libya implies the need to utilise a statistic
approach which allows for obtaining quantitative evidence and gaining rigorous findings.
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5.6 Research Strategy
The research strategy is a methodological inquiry by which meaningful research can be
carried out in order to respond to certain goals. As asserted by Saunders et al. (2016), the
research strategy should be in line with the philosophical assumptions adopted for the
study, so as to ensure consistency and harmony between the research design and
consequently, realise robust results. This also implies that an appropriate research strategy
decision is made on the basis of research objectives, taking into account the time limit,
resources available as well as research experiences (Bryman, 2015). Reviewing the
relevant literature reveals that there are a wide range of research strategies that exist in
the knowledge fields. According to Saunders et al. (2016), there are five different types of
research strategy: experiment, survey, case study, action research and ethnography.
Denscombe (2010) further divides this group into two strategies of grounded theory and
phenomenology. Furthermore, Yin (2014) suggests history and archival analysis to be
among the research strategies which facilitate the conducting of research, especially
regarding historical events. However, Yin (2014) has been criticised for ignoring key
research strategies such as action research and ethnography in his classification, despite
their importance in relevant research studies. Nonetheless, the critical issue remains as to
whether or not the research strategy adopted is able to deliver the desired data by which
the planned targets are achieved.
In relation to this understanding, research strategies as summarised by Sexton (2003), can
be incorporated into a research philosophical continuum, as shown in Figure 5.4.
Figure 5.4: Research Strategies Incorporated into Philosophical Stances. (Adapted from Sexton, 2003)
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As shown in Figure 5.4, a range of research strategies can be adopted based on the
philosophical continuum, namely ontology, epistemology and axiology. This includes
experiments, surveys action research, ethnography, and case study approaches. A brief
review of these strategies is presented as follows:
Experimental Studies Strategy
The experimental research is a study that closely adheres to a scientific research design.
However, the term of experimental study has a wide range of definitions. In the strict sense,
experimental research is what is called a true experiment (Yin, 2014). There are three key
types of experiments identified by Yin (2014): laboratory experiments, field experiments,
and natural experiments. Typically, an experiment is designed to examine the influence and
relation between variables in certain quantitative phenomena by controlling the tools,
participants and environment. The scientific experiment is established based on a
hypothesis that can be manipulated by the researcher, and variables that can be measured,
calculated and compared (Yin, 2014). The data then is collected, and results are presented
to determine whether to support or reject the hypothesis. An advantageous aspect of
experiment research is that it has an objectivist stance and is value free, so that makes the
outcomes more valid, and reliable. As the ontological assumption of this study leans
towards the relativist stance, the use of experiments is unjustifiable. Experimental studies
are carried out in certain environments that are controlled and in which the context and
the phenomena are separated.
Survey Based Studies Strategy
Survey study is a type of research strategy which is valuable to social science, involving the
collection of evidence from a specific sample of elements drawn from a defined population
(Saunders et al., 2016). There are various survey techniques a researcher can adopt. These
techniques are broadly distinguished into two types according to instrumentation and
according to the span of time involved. One technique includes the questionnaire and the
interview, whilst the other is comprised of cross-sectional surveys and longitudinal
surveys. Cross-sectional surveys involve the collection of data at a single point in time from
a sample drawn from a specified population. This strategy is used to document the
prevalence of particular characteristics in a population. By contrast, longitudinal surveys
aim to collect additional evidence from independent samples drawn from the same
population at more than one point in time. Whilst the main advantage of using surveys is
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that a large amount of data is generated, there is a primary limitation of survey research,
where surveys are deemed relatively expensive and time-consuming. However, many cost-
saving approaches can be implemented (Maxwell, 2008). Saunders et al. (2016) is of the
view that surveys can test phenomena, but their ability to investigate the context is still
questionable. In contrast, as reported by Maxwell (2008), the combinations of both
quantitative ‘questionnaires’ and qualitative ‘interviews’ data can be highly beneficial,
allowing a researcher to meet various aims. This study, therefore, adopts a survey-based
study strategy because it concerns sustainability interventions in the housing sector which
requires the researcher to be engaged with as many stakeholders from different
perspectives in order to customise a set of criteria for sustainable homes in Libya.
Furthermore, this strategy helps to verify and generalise the research findings. Therefore, a
survey-based study strategy is considered the most suitable research strategy that can
deliver efficient evidence needed to address the research objectives. Thus, the decision to
adopt a survey-based study has been justified in this section by considering the nature of
the study and its philosophical assumptions, and more justification for this choice is
provided in the subsequent sections.
Case Study Strategy
A case study strategy as defined by Yin (2014, p.18) is “an empirical query that investigates
a phenomenon within its real-life context, especially when the boundaries between
phenomenon and context are not clearly evident”. As such, adopting a case study can assist
researchers in investigating the phenomenon, allowing them to gain an in-depth picture of
the relationships and processes within the phenomenon. The case study has the ability to
provide various evidence through observations, documents, artefacts, questionnaires and
interviews, but as Yin (2014) points out, the case study strategy is shown to be strictly
close to qualitative approaches. According to Yin (2014), case studies can be carried out
with three different purposes: exploratory, descriptive and explanatory, in which a
researcher can employ single or multiple case designs, either holistic or embedded. As
reported by Yin (2014), a case study strategy is suitable in the case of questions related to a
contemporary set of events over which the researchers have no control, allowing
researchers to investigate the relevant problems from different aspects and various levels
in which in-depth evidence can be generated. However, this particular study does not
intend to deeply explore the current practices related to sustainability in the housing
sector; instead, it mainly seeks to investigate various perceptions of the sustainability
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phenomenon related to housing investments, and therefore the case study strategy is
deemed unsuitable for this research inquiry.
Action Research Strategy
The aim of adopting action research is to contribute regarding practical problems in an
immediate situation and towards the goals of social science by joint collaboration within a
mutually acceptable framework in order to enhance current practice (Carr, 2006). The
development of the action research strategy, as reported by Day et al. (2006), was
established in the education domain. Action research strategy is described as iterative
activities involving a range of continuing actions such as diagnosing, planning, and
evaluating (Saunders et al., 2016). The participants in action research have a critical role,
conceiving the practice with the aim to reform performance as well as improving their own
understandings (Day et al., 2006). Despite delivering in-depth evidence regarding the
phenomenon being researched, action research strategy would not be a suitable strategy in
this study because it is not the intention of this research to evaluate the in-depth current
practices of the housing sector nor to influence the attitudes of the participants; instead, it
seeks to explore applicable sustainability-based indicators.
Ethnography Strategy
Ethnography as a social science research strategy concerns the description of people or
small-scale societies by considering the researcher ethnographer as a research instrument.
As defined by Harris and Johnson (2000, p.13), ethnography is “a written description of a
particular culture - the customs, beliefs, and behaviour - based on information collected
through fieldwork". Saunders et al. (2016) define an ethnography study as a strategy that is
“highly time consuming and takes place over an extended time period as the researcher
needs to immerse herself or himself in the social world being researched as completely as
possible”. This study does not intend to study physiology or behavioural patterns of the
participants or understanding of the culture of a population, rather, it is concerned with the
construction of experts’ perceptions of the most effective sustainability based interventions
in housing projects, and hence, the ethnography strategy is not suitable for this study.
5.7 Time Horizon
The time horizon layer, as described by Saunders et al. (2016), has been divided into two
types, namely cross-sectional and longitudinal. This classification was determined based on
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the time period involved for the research to be carried out. In this regard, the study can be
classified as a cross-sectional study, which is limited to particular times and a particular
phenomenon (Saunders et al., 2016). Although the research instruments applied are
distributed at different points in time, these techniques are concerned with the same study.
The approach, therefore, remains a cross-sectional study. In contrast, a longitudinal study
allows for data to be collected at more than one point in time in order to examine a
particular phenomenon and control changes and development over time (Saunders et al.,
2016). The study therefore does not consider examining changes of a particular
phenomenon over a particular time, rather it is bound to a time schedule of PhD studies, so
this means cross-sectional is the time horizon of the study.
5.8 Research Techniques and Data Analysis
Having discussed various philosophical assumptions, methodological approaches as well as
the research strategy adopted along with identifying the time horizon, the foundations are
now laid to be able to discuss the research techniques adopted for this study. It is
suggested, based on previous understanding, that a focus group interview and
questionnaire are sufficiently appropriate to fully accomplish the research targets in this
study. These techniques will be the focus of the discussion through the upcoming sub-
sections, followed by addressing the analysis tools and strategies adopted to report the
results of this research.
5.8.1 Research Techniques
The study as mentioned earlier has adopted a pragmatic methodology which allows for the
use of both qualitative and quantitative evidence. From this perspective, a focus group, and
questionnaire survey have been subsequently conducted since it was evident that they
were suitable for gaining a response to the research queries.
5.8.1.1 Focus Group Technique
Focus group interview is considered as the first empirical research method to be used
through the ongoing study. Focus group technique has become one of the principle
research techniques used in business and management, providing insights into how people
think and obtaining a deeper understanding of the phenomena being studied (Litosseliti,
2003). It is highly recommended that to gain deep and rich data, the focus group should be
designed in a proper manner using an adequate number of participants with the aim of
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establishing a rigorous focus group session to ensure investigating the phenomenon being
researched.
Intent and Justification
This study aims to conduct a single focus group interview in order to reinforce the
discussion undertaken through the literature review and guiding the objectives of data
collection from the next step of the questionnaire. As reported by Saunders et al. (2016),
the adoption of focus groups particularly in exploratory research can facilitate designing
the subsequent phases of surveys through identifying the required questions that should
be delivered. However, the technique of focus groups has been adopted instead of just
individual interviews because the latter was not advisable as it was considered insufficient
to deliver the desired data which tends to be normative in essence (Litosseliti, 2003). The
economic perspective is critical, but other benefits from adopting focus groups will be
raised if it was compared to interviews. Whilst it can be beneficial to generate in-depth
data, conducting interviews seems an expensive proposition that can exceed the available
resources, whilst focus groups can give the researcher the ability to more economically
capture deeper data than individual interviews (Boyce & Neale, 2006). In addition, as
Boyce and Neale report, group interaction and non-verbal communication are other key
advantages of focus groups. The interaction between interviewees in focus groups can
effectively encourage and promote best solutions and suggestions whilst highlighting any
similarities or disagreements between viewpoints (Boyce & Neale, 2006). Litosseliti (2003)
goes further to assert that the focus group is an ideal instrument to generate ideas through
brainstorming sessions and achieving a shared understanding of the examined
phenomenon. Non-verbal communication is also vital data that is captured through holding
a session of focus group. Interviewees in focus groups often react differently to certain
issues (Litosseliti, 2003). This type of interaction can provide significant data reinforcing
the analysis process. As such, the focus group as pointed out by Cooper (2011), allows the
researcher to observe the way in which participants collectively make sense of an issue
while constructing meanings around it. Furthermore, typical interviews fundamentally
depend on the moderator ‘researcher’ who manages the session of interviews through his
or her questions which more often delivers unconscious cues to the participant thereby
influencing the responses in a particular way (Boyce & Neale, 2006). In the avoidance of
such bias, the researcher was eager to remain neutral and to not offer hints nor suggestions
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that might affect the participants’ views. Therefore, the main rationale for the adoption of
the focus group technique was to overcome the disadvantageous aspects of the interview,
allowing the participants to fully engage with the phenomenon under consideration, as
advocated by Litosseliti (2003), and obtaining a great level of consensus regarding the
themes examined, whilst it allows the researcher to compare and complement the results
(Boyce & Neale, 2006). On the other hand, it might be argued that other methods such as
the Delphi questionnaire is appropriate for this phase of the study. The basic idea of Delphi
studies is to use expert opinions in iteration processes to solve the problem and to use
anonymous feedback (Linstone & Turoff, 2011). It has believed that through frequent
responses, the information returned as feedback results in a better judgment than a simple
questionnaire. The preference between the method of the Delphi survey and the focus
group, as argued by Loo (2002), depends on the characteristics of the research subject, the
structure of the group of experts and the present framework conditions. For this study
which seeks to customise a set of sustainability-based criteria for housing projects, the
focus group is at an advantage compared to the method of Delphi survey because the
former allows more space for discussion and brainstorming between participants than
those in the Delphi questionnaire. Moreover, the Delphi questionnaire would have been too
time consuming and seems riskier because of the potential drawbacks of the Delphi
technique as absorbed by Linstone and Turoff (2011). As such, taking into account these
attributes, the focus group technique is deemed more preferable for this study.
Nonetheless, the focus group in turn has some disadvantageous aspects, especially related
to the moderator, the person who facilitates the focus group session. The moderator plays a
critical role in focus groups. A well-skilled moderator is able to promote and guide
discussions in accordance with the desired targets whilst a poor moderator dominates the
conversation and prevents the participation or loses the focus of discussion. The optimal
control over the focus group session, however, is not easily achieved by the facilitator as
the tendency for the interviewees to move away from the point of the research remains
high (Boyce & Neale, 2006). This disadvantage, however, can be overcome if a facilitator is
well-skilled in relation to the session management. The moderator, ‘the researcher’, in the
focus group can benefit from being a lecturer enabling them to manage the session in a
sufficient manner. The justification for choosing the focus group for this phase, therefore, is
that the participants are more likely to express different perceptions towards sustainable
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homes, whilst the interaction and dynamics occurring between those participants would
allow for effective sharing of their knowledge which eventually optimises the outcomes.
Design and Data Collection
The primary aim of conducting a single focus group interview was to collect data about the
most effective interventions related to sustainability in housing investments and to use the
results to construct the subsequent phase of the large-scale questionnaire. In this sense, the
focus group agenda has held a fourfold objective, including: (i) examining the position of
the sustainability assessment in the housing sector in Libya; (ii) investigating the current
practice delivered to assess the housing investments; (iii) investigating the main features
that have been over-looked or underestimated within the prevalent schemes; and, (iv)
delivering the most important sustainability-based features which are characterised in the
Libyan built environment. These themes have been designed to be delivered in the form of
open-ended questions as this can promote discussion in the focus group session (Boyce &
Neale, 2006). The facilitator in the focus group session, as suggested by Saunders et al.
(2016), should prepare an organised script for the focus group session in order to explain
to participants the targets, rules, and other information that is thought to be important.
Thus, the researcher prepared a script for the session of the focus group which put the
participants in the situation and made clear the duties and rights that should be
considered. Additionally, as suggested by Litosseliti (2003), the location that the focus
group is intended to be held in, should also be safe, comfortable and adequate for
conducting a conversation. To ensure this, the focus group was held in the University of
Tripoli in a convenient, integrated hall (see Section 6.2.1, p.136 for a detailed discussion of
design and procedure).
Sampling Quality and Size
Another critical issue raised is who should be involved in this discussion and the structure
of the focus group sample. As Bryman (2015) reports, establishing the expertise of the
participants affects the quality of the outcomes. In contrast to quantitative research, as
asserted by Bryman and Bell (2015), the sampling in research with a qualitative
perspective is less significant as this concerns more the quality rather than the quantity.
Again, according to Cooper (2011), a focus group does not utilise random or probability
samples, instead, it is more likely to follow a purposive sampling strategy. Random samples
give the chance of each subject in the entire population to be equally selected. By contrast,
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in non-random samples, the chance of each subject being selected from the population is
not equal. The purposive sample as a sub-set of non-probability sampling, encompasses
members with characteristics of the overall population helping to gain greater insights into
the phenomenon being researched (Cooper, 2011). Purposive sampling, as defined by
Cooper (2011, p.167), is “a research sample that allows researchers to choose subjects for
their unique characteristics or their experience, attitudes or perceptions”. The purposive
sample is generally employed to examine precise demands that need specific conditions for
potential participants where this query is not possible to be achieved with a random
sample (Creswell, 2013b). From Saunders et al.’s (2016) perspective, purposive sampling is
a technique for selecting members who can enable researchers to achieve efficient
responses to their research questions.
With this understanding, the sample for the focus group interview was purposely selected.
The rationale for adopting a purposive sample is that the study looks for experienced and
knowledgeable academics and professionals whose core research subject is sustainable
homes. The potential participants can be selected by designing a set of criteria that should
be met for participation requirements in accordance with the study query (Creswell &
Clark, 2011). A review of published studies (e. g. Bryman, 2015; Cohen et al., 2013)
highlights a range of criteria of which experts should be qualified. This can include: (i)
publications in the field; (ii) signs of professional eminence such as leadership,
membership, or holding office in a professional society or organisation; (iii) peer judgment
and recommendations; (iv) honours by professional societies; (v) self-rating of the
expertise in the relevant area; (vi) presentations made at national conventions; (vii)
relevant years of experience; (viii) selection for comment by national or regional media on
relevant issues; and, (ix) the number and importance of patents held. Therefore, it is
important to carefully design the group expertise to ensure that the focus group generates
rigorous results.
In light of this background, participants for the focus group have been selected based on 1)
expertise in sustainability and housing investments so that they have all participated in at
least two into journal articles, conferences related to the subject area; and 2) interest in
developing criteria for sustainable homes. Therefore, the participants are supposed to not
only have theoretically thought about the concept of sustainability, but they also were
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engaging within various actions associated with sustainability in built environment (e.g.
Aligning with this, as Saunders et al. (2016) reported, some participants are likely to feel
uncomfortable in expressing themselves in front of a group of people with whom they are
not familiar. As such, it is suggested that a sampling strategy of horizontal slicing, which
means selecting subjects from closely similar backgrounds, can be helpful to reduce these
adverse influences (Saunders et al., 2016). In consideration of these issues, the researcher
adopts a purposive sample of a homogeneous group of experts who are considered senior
practitioners, professors and administrators in the field of sustainability related to housing
investments from different sectors, namely industry, academia, and government.
Identifying the necessary number of experts in the focus group is another important issue.
The focus group, as Cooper (2011, p.719) states, is a “simultaneous involvement of a small
number of research participants who interact at the direction of a moderator”. However,
the literature has no consensus on the number of participants in a focus group. According
to Seidman (2016), the focus group usually involves two to four members while the
optimal size to promote discussion in a focus group is 5-12 participants according to
Bryman (2015). Given that there is no standard for the size of the focus group interview,
and number of responses on the researcher’s calls, the focus group was held with five
subjects who demonstrated the required expertise and knowledge as well as all of whom
were responsible for delivering aspects of sustainable development through their
organisations. In fact, the current state of Libya (post conflict) as well as limited time and
funds available are little conditions that have overweighed this sample size (see Section
6.2.1, p136 for a detailed discussion of procedure).
5.8.1.2 Questionnaire Technique
The questionnaire survey is a technique linked to the deductive approach, described as a
set of proforma questions which is distributed to identified subjects in order to generate
the desired data (Saunders et al., 2016). This type of survey helps researchers to collect a
large amount of data from a wide research sample (Cohen et al., 2013). It is recommended
that to gain wide and reliable evidence, the questionnaire should be designed in a proper
manner using a suitable sampling strategy to ensure a rigorous questionnaire is
established that can satisfy the investigation of the phenomenon in question.
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Intent and Justification
This stage of the questionnaire aims to verify the results obtained from the previous stage
of the focus group, which are related to the customisation of the most applicable categories
and criteria for assessing sustainability in Libyan home investments. The questionnaire is
considered one of the most common approaches to data collection (Saunders et al., 2016;
Cohen et al, 2013; Creswell & Clark, 2011) in which researchers devise a set of written
questions before distributing them to the target group. Data collected by using a survey
technique can provide several possible explanations for the phenomenon of interest
(Creswell & Clark, 2011) and it also has a number of advantageous aspects. For many, the
questionnaire as a data collection tool, is relatively easy to implement with a wider
coverage (Cohen et al., 2013). Using questionnaires as reported by Cohen et al. (2013) can
minimise the participants’ pressure compared to interviews, which allows subjects to
freely express their views and perceptions. Otherwise, there are potential disadvantages
for using questionnaires including, the low response rate or the incompleteness and the
difficulties of checking the truthfulness of respondents' answers (Creswell & Clark, 2011).
However, these obstacles can be overcome or alleviated if the researcher designs their
research well and follows a rigorous procedure of rules in relation to research tracking
(Saunders et al., 2016). Therefore, the primary objective for the use of the questionnaire at
this stage is to engage with as many experts from industry, academia, and government
sectors which are related to sustainability in the Libyan housing projects with the aim of
obtaining the perceived importance and drawing up the ultimate balance of sustainability
needed in the housing investments.
Design and Data Collection
Researchers have several options to design the questions of the questionnaire. Saunders et
al. (2016) report that the choices among different questionnaire types can be influenced by
several aspects such as the research objectives, respondents’ characteristics, sample size,
and the number and types of questions. In this way, scholars (e.g. Bryman, 2015; Gray,
2014; Creswell & Clark, 2011) distinguish between three types of questionnaire, namely
structured, semi-structured and unstructured. Structured questionnaires ask closed-ended
questions and are mainly used with the quantitative perspective. By contrast, unstructured
questionnaires are completely open, whilst semi-structured questionnaires use both close
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and open-ended questions. According to Gray (2014), questionnaires can be divided into
two further nodes, descriptive and analytical. Descriptive questionnaires are designed to
investigate the characteristics of a certain sample with the aim of identifying the variability
in a phenomenon. Otherwise, analytical questionnaires seek to test a theory and to explore
the interrelationship between the study variables. For the purpose of this study, the set of
desired data from the questionnaire primarily concerns the collection of normative
evidence, as opposed to opinion-based data (e.g. gathering perceptions or understanding
meaning), which according to Field (2013), would advocate the use of structured, analytical
questions.
The questionnaire content was mainly informed by the results obtained from the focus
group conducted within the previous stage, covering the 43 criteria split up into the seven
categories of the sustainable homes assessment model, namely: Management and Process;
Materials and Recourses; Energy Efficiency; Water Efficiency; Waste and Pollution; Health
and Wellbeing; and Location Quality. The participants were asked to indicate the
importance of each criterion and define further criteria that are considered critical for the
evaluation of housing projects regarding sustainability in the Libyan context (see Section
6.3.1, p.153 for a detailed discussion of design and procedure). The questionnaire
developed in the study was initially divided into three parts:
i. Part one included the list of forty-three criteria identified from the earlier
investigation. These criteria were classified into seven categories;
ii. Part two included a list of the seven categories where respondents were required to
signal the level of their importance; and,
iii. Part three was related to general information of the respondent’s field, discipline,
qualification, experience, region and gender.
From another perspective, Saunders et al. (2016) classified the questionnaire in terms of
its distribution into two types, interviewer-administered and self-administered.
Interviewer-administered questionnaires are held when the subjects directly respond to
questions either face-to-face or via the telephone. While self-administered questionnaires
are completed by the subjects themselves through either the delivery by hand, postal
questionnaire, and web-based questionnaire. In this respect, according to Carter and
Fortune (2004), the web-based questionnaire has been increasingly in use since 1995,
providing a new medium by which research data can be collected more quickly, at a lower
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cost with a higher rate of return. Not only do web-based questionnaires reduce travel and
time costs, they also allow a wider sample of participants to be reached and for time to be
saved for experts whose available time is very limited (Couper, 2000). As reported by
Carter & Fortune (2004), one of the most important features of web-based surveys is that
the data is generated instantly in electronic format. This allows the researcher to have data
available earlier and it can be more easily transferred electronically into the analytical
tools. The weaknesses linked to online-based questionnaires seem to be common to the
other forms of survey (e.g. coverage and sampling, non-response, measurement, etc.).
According to Couper (2000), one prominent issue associated with this type of
questionnaire is sample selection. The potential participants in a web-based questionnaire
require access to internet which is not always available to some subjects. As such, this may
lead to a low response rate non-response bias (Couper, 2000). However, a non-random
sample like ‘convenience sample’, as adopted in this research, is flexible with a pre-
recruited list sample which allows the researcher to ensure higher response rates. There
are ethical matters to consider with the use of online-based research. In its guidance
‘ethical decision-making and internet research’, the Association of Internet Researchers
(AOIR, 2012) emphasises a range of important aspects relevant to the field of Internet
Studies and the ethical perspective. As AOIR (2012) stress, the privacy issue is one matter
that emerges with the use of internet research. Since web-based research is likely to be
conducted across different countries with various ethical standards, Carter and Fortune
(2004) suggest researchers should recognise these issues in their studies. In this respect,
the researcher obtained ethics approval from the Research Ethics Guides issued by the
University of Salford and confidentiality and anonymity were maintained in all stages of the
research. A web-based questionnaire mode was adopted to distribute the questionnaire to
the targeted sample. The questionnaire was issued in electronic format via a commercially
available online survey application. Indeed, the development of communication technology
and the spread of the internet have allowed for expanded sampling of research to be
conducted more easily and reaching a wider spectrum of views on the subject area being
researched.
As recommended by Field (2013), a pilot survey is vital to evaluate the clarity and
comprehensiveness of the questionnaire, as well as the feasibility of the survey as a whole.
The proposed questionnaire was initially tested by particular participants to test the
context and consent of its design and to investigate the precision of questions being asked
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and to establish suitable questions to provide the required information and establish the
final questionnaire. The questionnaire was piloted, recruiting 45 participants to gain their
feedback and thus, devise the final version of the questionnaire. Piloting the study allows
the reliability of the instrument to be tested through employing Cronbach’s Alpha. Given
that no significant matter emerged from this stage, as suggested by Field (2013), the
collected data from the pilot study has been included in the main study data set. (see
Section 6.3.1, p.153 for a detailed discussion of procedure).
Sampling Quality and Size
Since the first step in the selection of an appropriate sample is the determination of the
population of the study, it is necessary to clarify the extent to which the total population
actually is representative (Bryman, 2015). The population can be identified by those who
are engaging within the phenomenon of interest (Bryman, 2015). As mentioned earlier, this
study aims to define the most applicable categories and criteria for assessing sustainability
in home projects in Libya. Various groups of specialists involved in the house building
process will be consulted, including: Architect, Quantity Surveyor, Structural Engineer, Civil
Engineer, and Construction Manager, all of whom have traditionally been the major
specifiers (Emmitt & Yeomans, 2008). Bearing in mind that the analysis unit in this
research is the Libyan public house projects, it can be argued that the population of the
study encompasses all local and international professionals, contractors, consultants,
academics, etc. who are involved in activities related to the implementation of
sustainability within the Libyan home projects. Based on this understanding, it is quite
difficult to pinpoint or speculate the size of the research population because it has the
probability to merge a very wide variety of subjects. In this case of an infinite size of
population, consequently a known portion of the population was excluded so that non-
random sampling strategies were adopted in this research. It might be argued here that
selecting a research sample randomly would be beneficial for this study, however, Sapsford
(2007) advocates that representativeness, which is the ultimate target for any sampling
strategy, may also not be achieved even with the use of random sampling.
Both Bryman (2015) and Creswell (2013) suggest that researchers should always aim to
narrow the population’s scope and purpose; it is essential that the research sample should
be designed carefully to represent the entire population and, as such, it must sufficiently
reflect the population’s characteristics. One of the most common types relevant to the non-
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random sampling strategy is “convenience sampling”. This strategy was adopted not
because such sampling strategy is necessarily easy to recruit, but because it is often used
with whichever individuals are available rather than selecting them from the entire
population. Furthermore, limited time, funds and data available as well as the current state
of Libya (post conflict) and the risk associated with collection of data to some extent, have
made it necessary to adopt this sampling strategy. To reinforce the choice of convenience
sampling and its representativeness, the research sample was designed to thoroughly
match the national distribution of public housing projects as closely as possible. In this
regard, the researcher first used the database of the Libyan Institute of Architects (LIA), the
database of the housing projects from the Organisation for Development of Administrative
Centres (ODAC) and the database of the academics in the Libyan universities. Whilst the
convenience sampling strategy adopted in this research may have increased the possibility
of bias arising within the sample, as noted by Sapsford (2007), the adopted strategy
prevented the construction of an unrepresentative sample whilst improving homogeneity
and accuracy of data, thereby enhancing the validity of the results.
Another critical aspect is the determination of the sample size. As previously
demonstrated, an infinite size of population leads the sample size to be influenced by the
number of variables given. According to Costello and Osborne (2005), a majority of survey
study researchers perform analyses with subject to item ratios of 10:1 to 5:1 as a minimum
to be accepted. In this research, once 43 factors were identified for sustainable homes,
based on the item ratio method, a minimum sample size of 215 (43⨯5) was determined.
However, in a pessimistic scenario, Field (2013) asserts that the typical response rate will
be in the order of 20-30%, yet, when this is compared with the response rates achieved in
research seeking to collect data from built environment professionals based in Libya,
returns of 30-35% appear typical (Gherbal, 2015). As such, the researcher assumed a
return rate of 30% for this survey. To generate the targeted figure, bearing in mind the
anticipated 30% return rate, it was determined that a survey sample of 1050 was required.
As a result, however, the researcher distributed 1125 web-based questionnaires amongst
potential participants in the national housing associations, universities, and housing
providers (as determined earlier). Additionally, facilitated by websites for the relevant
organisations as well as social media to obtain the contact details, the researcher started
sending individual e-mails to the potential participants to invite them to take part in the
survey. Ultimately, a total of 315 (7:1) responses, including 45 piloted subjects, were
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received with no missing responses, as the respondents were electronically pushed to
complete all the questions required (see Section 6.3.1, p.153 for a detailed discussion of
procedure).
5.8.2 Data Analysis Strategy
Data analysis is considered one of the key milestones in any research study because it
illustrates and inspects the evidence collected through the research process so that
conclusions can be reached. As explained by Saunders et al. (2016), the data analysis
process includes a set of actions by which the primary research targets are to be achieved.
This encompasses summarising, testing, classifying and reporting or in some cases,
recombining the quantitative and qualitative information. As further pointed out by
Saunders et al. (2016), the research analysis procedure must be consistent with the
philosophical assumptions and methodology adopted. In this sense, to reduce potential
analytical difficulties, as Yin (2014) stresses, researchers should organise a clear strategy
for data analysis to ensure using appropriate analytical tools that serve the ultimate
research goals. Nonetheless, key literature (e.g. Saunders et al. 2016; Bryman, 2015; Yin,
2014; Field, 2013) reveals that no clear methods or tools have been customised for
conducting a specific analysis of the data, even though there are extensive analytical tools
relevant to various methods. For this research, as discussed earlier, pragmatic philosophy
in line with exploratory sequential mixed methods strategy was chosen as an appropriate
method in this study. As a result, the process of analysis commenced firstly with the
qualitative data analysis of data generated from the focus group, which later was used to
establish the research stage of the quantitative questionnaire. The second analytical phase
is analysing quantitative data collected from the questionnaires, then the findings from
both qualitative and quantitative results are collectively discussed at the end of these two
phases. A detailed discussion of these two analytical techniques are presented in the
subsections that follow.
5.8.2.1 Focus Group Data Analysis
Employing the focus group technique generates qualitative data in the form of free-flowing
text. For analysing such data, an array of methods has been suggested within the literature
pertinent to qualitative analysis. As stated by Mohamed and Ragab (2016, p.6), six
prominent tools are typically used in the analysis of qualitative data, including thematic,
content, structural, interactional, performative and discourse analysis:
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➢ Thematic Analysis; this technique seeks to search for various themes that are
recognised as being significant for describing a phenomenon. It is useful for
combining meanings and finding common patterns across participants’ perceptions
(Braun & Clarke, 2006). Thematic analysis is a qualitative analytical tool that searches
for various themes that are recognise as being significant for describing the
phenomenon under investigation (Fereday & Muir-Cochrane, 2006). Therefore, this
type of analytical tool can be suitable for the purpose of this study with the aim of
aggregating the most applicable sustainability-based interventions in housing
projects.
➢ Content Analysis; this technique concerns word patterns, repetition, and
relationships between subjects. It is usually employed when large volumes of text
emerge and provides only quantitative accounts (Vaismoradi et al., 2013), so this
technique is not preferable for this study, which is designed on the basis of a small-
scale focus group.
➢ Structural Analysis; this technique focuses on the narratives emerging amongst the
subjects through synthesizing the words to construct meaning. It is useful in the case
of narrative-based research (Riessman, 2005). In spite of the structural analysis
technique being beneficial to build up patterns of perception and understanding, it is
not suitable in the case of developing a set of criteria for sustainable homes on the
basis of a normative framework where the objectiveness is fundamentally significant.
➢ Interactional Analysis; this technique emphasises the interaction between
participants where both the speaker and listeners collaborate to develop meaning.
Unlike for this study, an interactional analysis approach is suitable for studies of
relationships and interactions between subjects (Nielsen, 2009).
➢ Performative Analysis; this technique extends the interactional analysis technique,
going further to capture both verbally and non-verbally metaphors influencing
subjects through the study session. It is preferable in the case of communication-
based research (Riessman, 2005). Therefore, performative analysis technique is
unjustifiable for this study as its nature is not relevant to sustainable development in
construction.
➢ Discourse Analysis; this technique reveals the actual words used to deliver meaning.
It primely looks at the way concepts are expressed to examine subjects’
sociopsychological characteristics rather than the text structure, so that it is suitable
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in disciplines like philosophy and linguistics (Alvesson & Karreman, 2011). Again, this
technique cannot be justified as this study is in the field of built environment.
It is evident therefore that the most suitable technique is thematic analysis to conduct the
qualitative analysis for data generated from the focus group in this study. As mentioned
earlier, thematic analysis is a systematic analysis seeking to capture themes and patterns
within the text (Borrell, 2008). According to Braun and Clarke (2006), thematic analysis is
one of the most common qualitative analysis techniques due to a range of advantageous
aspects. One of these advantages, as both Bryman and Bell (2015) and Vaismoradi et al.
(2013) advocate, thematic analysis is uncomplexity as well as its flexibility which suits
analysing complex phenomena, can potentially reflect on rich outcomes from the analysis
process. By contrast, thematic analysis as stressed by Vaismoradi et al. (2013), is highly
dependent on the researcher’s expertise so that it is likely to be inconclusive if not applied
correctly. Vaismoradi et al. (2013) go on to explain that in such cases, the poor results are
due to the failure in conducting analysis or the choice of questions that are designed
improperly rather than the tool itself.
To ensure an idealistic performance and reduce potential difficulties in the application of
thematic analysis, establishing an analytical process strategy is critical, as asserted by Yin
(2014). Qualitative data reduction is the key to the analytical strategy in a way that allows
summarising and transferring the findings discussion into a meaningful report through a
manageable form. In light of this, Braun and Clarke (2006) point out six key steps guiding
researchers to perform thematic analysis properly, as shown in Figure 5.5.
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Figure 5.5 The Six Step Process Thematic Analysis. (Adapted from Braun & Clarke, 2006, p.87)
The researcher in this analytical phase found the six-step guidance suggested by Braun and
Clarke (2006) helpful. A brief overview is presented as follows:
In the first step all the data collected from the focus group was transcribed from the initial
audio form into textual version. The whole transcribed text then was translated from the
original language of Arabic into English. The final draft of the script was thoroughly
reviewed, and each interviewee was given a unique code to reference the quotations
selected properly. Once the textual script became familiar, the researcher in the second
step, applied initial coding to distinguish prominent keywords emerging in the qualitative
data. An Excel sheet in this step was also used to facilitate the process of thematical
analysis and classify the data aggregated, placing all the codes into themes and sub-themes.
In the third step, attempts were made to aggregate the similarities into one cluster, which
then assisted in the creation of subset nodes. Thematical analysis and the theoretical
framework, as suggested by Braun and Clarke (2006, p.8), can “match what the researcher
wants to know”. In addition, the conceptual model developed through the previous stage
significantly facilitated the process of drawing out the clusters and nodes, and the
researcher had no intention to reorient these themes, rather he left the coding process to
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do so. Having identified the initial clusters and nodes in the fifth step, these were revised to
make sure that the defined themes and sub-themes were properly established. Finally, all
themes and sub-themes along with the quotations were brought together in order to make
sense of the analytical process and present the final report of the qualitative analysis. The
resulting information of this stage was used to design the following phase of the
questionnaire survey.
5.8.2.2 Questionnaire Data Analysis
The questionnaire survey which generated qualitative data has been analysed via various
statistical tools in line with the measurement tool adopted within the questionnaire design.
The five-Likert scale as a common measurement tool is considered the most commonly
used technique for scaling data in questionnaires, providing the respondent with a number
of possible options from which to make a selection (Field, 2013). Whilst it must be
acknowledged that such an approach to question design restricts the respondent’s ability
to express their attitude and therefore, limits the polarity of the responses (Yin, 2014), it is
more likely to reinforce the reliability of the survey technique (Field, 2013). The
questionnaire designed for this stage of study used closed-ended questions, employing five
hierarchical levels of agreement, as advocated by Saunders et al. (2016) as being more
likely to present higher mean scores of responses relative to the highest possible attainable
score, as opposed to other methods that adopt measurement tools with 10 levels as an
example.
For the purpose of this research, a five-scale hierarchy of “importance” was adopted to
capture the degree of importance of the variables examined. This, as stated by Saunders et
al. (2016), can allow the participants to clearly express their perceptions with an adequate
level of agreement with the statements given. Indeed, the choice can be justified on the
basis of three reasons. First, it is much easier for the researcher to analyse the data and for
the potential participants to stay focused on the statements given and carefully respond to
the questions. The second reason is to facilitate a reliable comparison with previous
attempts which followed similar techniques, such as Alyami et al., (2013), Ali and Al
Nsairat, (2009) and Almansuri et al., (2009). Thirdly, the initial purpose of conducting a
questionnaire was to consolidate and refine the theoretical model developed through the
focus group, which would be followed by the phase of AHP ‘Analytical hierarchy Process’ in
line with the ten-scale measurement tool for ranking the set of criteria raised. Therefore,
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the five-hierarchy scale (i.e. not important; moderately important; not sure; important;
extremely important) is preferable in this stage of the questionnaire.
To calculate the relative weighting of the responses, as suggested by Saunders et al. (2016),
degree 1 was assigned for option ‘Not Important’, whilst degree 5 was assigned for level
‘Extremely Important’. Table 5.1 portrays the five-Likert scale and its values assigned.
Table 5.1: The Five-Likert Scale and its Values Assigned
Scale Not
Important Moderately Important
Not Sure Important Extremely Important
Value 1 2 3 4 5
Based on the Likert measurement, the quantitative data generated from the questionnaire
has been analysed using the basic descriptive statistics. As defined by Shannon (2000),
descriptive statistics is a statistical analysis method for describing attributes in the social
sciences. The descriptive analysis encompasses frequency distributions; measures of
central tendency, such as means and median; and measures of dispersion like standard
deviation (Shannon, 2000). In this respect, nonparametric tests have been employed,
because the measurement tool adopted - Likert scale - is an ordinal scale with the aim to
examine the level of agreement and disagreement over each subject given. According to
Saunders et al. (2016), in business research, the three most frequently used tools of
statistical measurement are median, mean and Standard Deviation. Therefore, the data
collected from the questionnaire survey was analysed employing a variety of statistics,
including; Cronbach Alpha, Frequencies, Value of Mean, Standard Deviation, Value of
Median and Value of Kendall’s W.
i) Alpha Cronbach
The first process used in the statistical analysis is the Alpha Cronbach test. The scales used
in the data collected were checked for reliability through the pilot study, using Cronbach’s
Alpha to check for internal consistency and suitability of criteria contained in the
questionnaire for analysis. Cronbach's Alpha is widely used in social sciences and it is the
most common measure of internal consistency (reliability), particularly used for
questionnaires that utilise a Likert scale for question responses (Yin, 2014). Cronbach’s
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Alpha ranges from 0 to 1, and the measurement tool is considered to be more rigorous as
long as this indicator is closer to 1 (Field, 2013).
ii) Frequencies Distribution
The frequencies of the respondents’ characteristics were also calculated, describing and
determining the quality of the sample selected. The frequencies were presented in the form
of figures and percentages.
iii) Value of Mean
Value of mean indicates the average rating of the importance assigned to each subject. This
reflects the significance of each criterion and category. The judgement of agreement among
respondents that a certain criterion is either acceptable or not, as Alyami et al., (2013) and
Almansuri et al. (2009) suggest, can be established based on a value of mean that is equal
or above 3 out of 5 on the Likert score. As such, the degree of importance increases as long
as the Likert score increases, and vice versa.
iv) Standard Deviation
Standard deviation value indicates the response dispersion or opinion variation, showing
the extent to which values differ from the overall mean. Standard deviation takes values
from 0 to 1 where a low standard deviation value means that most of the subjects are very
close to the average, which reflects a powerful mean value. By contrast, a high standard
deviation means that the subjects are spread out, which means a poor mean value.
v) Value of Median
Value of median indicates the scale or pattern that scored the higher rate of responses, or a
probability distribution. As such, the median presents the mid-point of the data. To
determine the median value in a group of variables, the frequencies must first be arranged
in value order from lowest to highest, and the median value is the number that is in the
middle, with the same amount of numbers below and above. In this case, the median value
can take 1 to 5 in line with the Likert scale adopted.
vi) Value of Kendall’s W
Value of Kendall’s W reflects if there are statistically significant differences between the
various data sources. In this research and aligning with Higham’s (2014) suggestion,
Kendall’s W test was carried out to assess the significant differences between the various
participant responses which consist of three different parts, namely professors,
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professionals and administrators. Kendall’s W test sought to compare the means and
identified the level of agreement between the respondents. The closer the score is to 1.00,
the greater the agreement within the research sample.
The development of data management and statistical analysis tools aligned with the
advanced technology allow researchers to easily conduct a variety of statistical analyses,
the choice of which should eventually serve the targets of the study, according to Saunders
et al. (2016). SPSS software application was used to undertake the aforementioned
statistical analyses which helps the researcher to deal with complex data and process it in
simple steps without being too time consuming.
5.9 Overview of the Methodological Design
Having discussed each element of the methodological design from the underpinning
philosophical stances to the research techniques and analysis, which were demonstrated
and justified throughout the previous sections, the overall methodological design emerges
and was portrayed on the basis of Saunders et al.’s (2016) onion. (Figure, 5.6)
Figure 5.6: The Methodological Design
Research process then becomes clearer after a detailed discussion of the research
methodology and design. The research process is a road map, as Marshall and Rossman
(1999, p.40) state, “an overall plan for undertaking a systematic exploration”. This mainly
informs the overall approach to research and includes decisions about research methods
and techniques. To this end, along with the methodological considerations and the research
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objectives throughout this study, the research process has been drawn up to conduct
various theoretical and empirical investigations, as shown in Figure 5.7.
Figure 5.7: Research Process
A brief overview of this development is presented as follows:
Phase One: includes a comprehensive review of the relevant literature to understand the
nature of the sustainability assessment’s structure in the building field. Reviewing the
recent trends in this context is an essential phase of this study. Then, the use of proposed
criteria, derived from an integrated analysis of the most reliable building assessment
methods, is vital to show areas of convergence through the empirical stage.
Phase Two: uses focus groups through interviews with 5 experts involved in sustainability
programs in the Libyan built environment. The focus group is a preferred method to gain
meaningful insight into the interesting phenomenon, since it offers narrow but rich
qualitative evidence with an adequate number of participants.
Phase three: employs use of questionnaire survey to consult potential participants and
collect the desired data that answers the research questions. Questionnaire is widely
recommended to gain quantitative evidence, considered to be the most applicable method
due to its ability to generate rigorous data and ensuring arrival at a sort of objectivity and
generalization.
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Phase Four: includes multi-criteria modelling using Analytical Hierarchy Process (AHP) to
customise a weighting system for the developing model of building assessment. AHP can
play an important role in the development of a potential ranking system, as it has the
ability to reflect local needs and prioritise sustainable homes aspects on the basis of the
multiple dimensions defined. This method is based on a pairwise comparison technique to
prioritise each criterion and category, using MS Excel software to analyse the outcome
from the pairwise comparison.
Phase Five: involves testing the model developed through the study to ensure reliability
and robustness. For this purpose, a small-scale interview is suggested as a supplementary
method, examining all data collection from the literature and empirical research to verify
the applicability of LSHAM.
5.10 Chapter Summary
The underpinned philosophy and methodological considerations, a pragmatist stance in
line with an abductive approach facilitated by mixed methods methodology were
considered to be suitable for the nature of this study seeking to develop a set of
sustainability-based interventions relevant to housing projects. In line with this, focus
group and questionnaire techniques were considered preferable research instruments to
collect the desired quantitative and qualitative evidence required to build a robust
assessment model for sustainable homes based on the Libyan context.
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6 Data Analysis and Discussion
6.1 Chapter Overview
The aim of this chapter is to identify applicable assessment categories and criteria for
Libya’s sustainable homes. As explained in the previous chapter, this research employed
sequential mixed methods composed of focus group interview and questionnaire survey
for collecting data on sustainability practices to discover the most influential factors that
ensure successful interventions associated with the concept of sustainable homes. The
questions contained in the focus group were informed by the review of the literature and
the results obtained from the integrated analysis of the well-established assessment
systems (i.e. BREEAM, LEED, GBCA and DGNB), whilst the questionnaire was used to
confirm the findings with a large-scale sampling strategy. Detailed information on the
design and implementation of both the focus group and questionnaire along with the data
analysis and discussion of the findings are addressed and presented in this chapter.
6.2 Findings from Focus Group Interview
The empirical stage was launched with a focus group exercise with an expert group in the
field of sustainable homes relevant to the Libyan context. The process and analyses of the
data collected will be demonstrated through the sub-sections that follow.
6.2.1 Planning and Managing the Focus Group Interview
The focus group stage has been organised mainly to fulfil four major objectives:
• Reinforce the discussion undertaken through the literature review and investigate
the need to develop an applicable sustainability-based assessment schema for home
projects in Libya;
• Explore the current practice and level of feasibility applied to the decision making
process for the project investments;
• Investigate the main features that have been over-looked or underestimated within
the prevalent schemes; and,
• Provide up-to-date criteria that can guide the housing investment decision making
processes towards more sustainable homes in Libya.
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As discussed earlier in Section 5.8.1.1 (p.115), the focus group interview recruited five
panellists, using a purposive sample, as shown in Table 6.1, all of whom were responsible
for, inter alia, delivering aspects of the organisation’s overall development and quality. The
recruited participants have over two decades of experience within the area of
environmental development and sustainable assessment systems in construction. The aim
of sampling a range of senior professionals and administrators from different organisations
was to gain a deeply overarching insight into the phenomenon being researched and to
develop a set of sustainability-based indicators for homes in Libya. Participants in the focus
group interview were identified through internet searches and a request to take part in the
research was sent to each potential participant by email by the middle of February 2018.
The invention email was also, attached with an information sheet along with the interview
agenda and the consent form. Once each interviewee had confirmed their willingness to
take part in this exercise, the interview date, time and location were arranged.
Table 6.1: Profile of the Focus Group Participants
Participant Organisation Role Expertise Experience (Years)
FG01
Construction firm
Quality and Performance Development Officer
General practice 28
FG02
Housing Association
Housing Services Officer Housing Advice 25
FG03 Local Authority
Environmental Services Manager
Housing Service
23
FG04
Housing Association
Housing Manager Housing Service
22
FG05
Construction firm
Project Manager General practice 21
The focus group interview was held in a hall provided by the University of Tripoli on 5th
March 2018, and it took approximately two hours where voices were digitally recorded
with the consent of the interviewees. The focus group session commenced with a briefing
phase in which the interviewer explained the context of the study and its purpose. At the
end of the session, the opportunity was taken to recap on some of the main points covered.
The purpose of this debrief, as suggested by Field (2013), was to ensure that the
interviewees were comfortable with all the themes covered in the session and were not left
feeling tense or anxious. The session was transcribed and then translated from the regional
language ’Arabic’ into English by the researcher, which provided an opportunity for the
researcher to re-familiarise with the data as a first stage in the analysis process.
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6.2.2 Analysis of Focus Group Interview
Having transcribed the interview, the qualitative data were analysed using a thematic
analysis. In light of this, three main themes alongside sub-themes were extracted from the
data. In the following sections, the themes, sub-themes will be presented alongside
quotations and texts extracted from the interviewees - the code FG (followed by a Number
1-5) refers to the interviewee from whom the evidence quotations were taken.
6.2.2.1 The Position of Sustainability Assessment in Home Projects
The first strand to be explored sought to establish the understanding of the importance of
sustainable homes in the Libyan context. The literature review clearly showed that the
there is a lack of reliable data (e.g. research papers, social reports etc.) regarding the
assessment methods applied in the home projects in Libya. As expected, the participants
unanimously agreed on the fundamental need for a comprehensive scheme guiding the
decision-making process in home projects. A clear sign came from the Quality and
Performance Development Officer at a construction corporation, who confirmed that the
lack of available frameworks would prevent any meaningful sustainability appraisal of
projects:
“Of course, I believe indicators promoting housing quality or as it’s said code for
sustainable homes becomes a necessity in order to assess a project in terms of its impact
on either environmental, social and economic dimensions for the Libyan context, …”
(FG01)
This was also confirmed by the Housing Services Officer at a Housing Association, who
mentioned the need to develop the design of homes to comply with the sustainability
requirements:
“… raising the quality of life required sort of things that ensure a good place to live in.
And one of the most important things now is to give attention to the process of
reorientation of the home design”. (FG02)
There was, furthermore, a judgment by the Environmental Services Manager at a local
authority that their orientation to renovation has generated some benefits to the
community, although these seem to be underestimated.
"No one can deny that physical improvement is essential, but there are other
interventions that can extremely enhance the quality of people’s life, What I meant is . . .
the successful plan should give attention to issues such as the surrounding environment
whereby ensuring all basic needs are easily reachable". (FG03)
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However, one of the views expressed by the Housing Manager at a Housing Association
opined that, although he accepted the importance of sustainability, he felt it was still early
to put such a plan and commitment in place:
"To be honest, we [Local Authorities] have boundaries. We are unable to make a significant change with the current legislations that impede our efforts to make the
change we want. … the commitment to sustainability takes time notably without a clear
vision or framework. Our [Local Authorities] priorities in this phase are to face the
increasing demand on housing…”. (FG04)
In spite of the interviewees’ argument that the lack of usable sustainability scheme remains
a key difficulty in appraising projects, interestingly, the Project Manager at a construction
firm tempered his comment by suggesting that, whilst sustainability is desirable, the
bottom top approach remains a key driver to ensure fully commitment and
implementation:
”I see that introducing such orientations and embedding them within the firm’s culture is
not the role of that organisation itself… it’s the sort of integration the government level
should find a way to communicate with those [firms] to embed the desirable orientations
and at the same time it should open doors to develop the traditions that they
[government] are willing to embed… here it is not to say that the government should
have a rigorous and well-designed system that serves the desirable goals”. (FG05)
6.2.2.2 Current Practice Adopted
This section of the focus group sought to explore the current approaches adopted through
investigating the level of feasibility assessment applied to decision making processes for
the project investments. The literature review revealed that such an assessment would
often depend on a monetary focus, using merely capital cost or in some cases a life cost
analysis. The data analysed revealed a significant disparity between the acceptance of eco-
social and environmental care given through the industry’s practice and the actual need for
improving their implementation in practice rather than being rhetorically applied. The
participants from the Housing Associations have shown encouraging views upon
sustainability application in their business, reflecting their efforts to assimilate the concept
of sustainability into their investments:
"Housing Corporations work in an integrated manner… we [Housing Corporations]
take into consideration multiple dimensions through the process of decision making… I
can say, either intentionally or not we [Housing Corporations] have a sense of the
concept of sustainability in our business, going back three or four years ago”. (FG02)
"… to some extent that’s true, currently we [Housing Corporations] devoted ourselves to
developing [named] projects in terms of regenerating green spaces and play areas for
residents. We're trying to make people more comfortable with their properties as well as
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offering environmentally friendly products. However, the level we can achieve depends
on the funding we get”. (FG04)
Nevertheless, however, the Project Manager at a large construction corporation rejected
the views of the housing associations, commenting that they do not express the
commitment to sustainability as much as the monetary-based appraisal:
"We are required to undertake a capital cost assessment using the net present value to
reflect the revenues through the entire life of a project. This as we know, depends on
financial consideration being economically focused. We hardly do rigorous assessments
reflecting issues associated with social and environmental dimensions”. (FG05)
Regrettably, as the views of the Environmental Services Manager at a Local Authority
expressed, the feasibility assessment conducted which is considered critical to the
decision-making process, is fundamentally built upon a comprehensive approach covering
multiple dimensions associated with sustainability:
"The value assessment along with direct/indirect cost/benefit analysis were conducted
for all our projects.... this is supposed to cover all aspects socially, economically and
environmentally in order to ensure that we [firm] meet the desirable goals". (FG03)
The interviewees from the construction corporations opined that the project appraisal
lacks a comprehensive norm ensuring best practice in terms of sustainability. This,
according to the Quality and Performance Development Officer at a large firm, can be
traced back to the fact that the availability of expertise as well as the level of funding are
the two main factors preventing undertaking such comprehensive appraisal of projects:
"… it was allocated roughly 25,000 D.L for this purpose … no way! with this budget and
locally available experience… We [firm] do as much as possible to fulfil our mission in
light of our priorities" (FG01)
This view was also emphasised by a Project Manager at a large construction firm, who was
also of the opinion that the lack of funding for renovation towards such desirable targets
has held back ambitions:
"That’s evident, limited budget has significantly affected our plan for implementing any
ambitious targets". (FG05)
The Quality and Performance Development Officer once again expanded his point of view,
clarifying the boundary of responsibilities:
"… before judging the level of change achieved, we should firstly ask, was I [firm] given
the required budget. I’m always saying, stretch your legs according to your coverlet…
We are asked to get 100 percent achievement, but with paying zero extra… I can make a
significant impact, but you have to pay, as simple as that”. (FG01)
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The Environmental Services Manager exemplified further his view through an experienced
case study, obviously demonstrating the commitment to a sense of sustainability within
public home projects:
"… the whole residential area [named project in the city of Sirte] was completely renewed although the decision of demolition would cost less… We took into
considerations several aspects generating social, environment and economic benefits for
occupants and local community…". (FG03)
Interestingly, a Project Manager at a large construction firm suggested that enhancing the
corporate governance can bridge the gap between the current practice and the
expectations, implicitly revealing that the absence of usable frameworks might explain the
reasons why multi-dimensional assessments are not given an appropriate place within the
development of projects:
"...I think we need first to change the organisation culture that raises the financial returns from a project before promoting orientations that serve further dimensions such
as eco-social or environmental impacts… this remains a challenge as in reality we value
the firms solely based on the monetary side so that the lack of a suitable framework for
detailed appraisal or any efforts in this respect are so difficult”. (FG05)
6.2.2.3 Emergent Features of Sustainability in Libya
The final major theme within the focus group sought to confirm the main features of
sustainability and explore any additional emerging criteria that are to be applicable for
sustainable homes in the context of Libya. The literature review along with the integrated
analysis conducted have clearly shown that there are seven major themes (i.e. Management
and Process, Materials Efficiency, Energy Efficiency, Water Efficiency, Waste and Pollution,
Health and Wellbeing, and Location Quality), split into 44 criteria, as shown in Table 4.3
(p.90). The participants were asked to examine these indicators before being asked to
suggest any further indicators that are applicable to the Libyan housing context.
6.2.2.3.1 Existing Features of Sustainability
To facilitate this section of the research, the panellists were provided in advance with an
index of the criteria delivered from the previous stage of integrated analysis of the four
well-established methods (i.e. BREEAM, LEED, GBCA, and DGNB). Then, the interviewees
were asked to give their opinions on the set of categories and criteria suggested through
the theoretical model developed through this study to examine the main indicators.
Findings from this phase of the analysis show that the number of criteria aggregated within
the integrative data analysis scheme are not quite applicable for the Libyan context,
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resulting in 38 emerging indicators which received consensus amongst the participants.
Due to the extensive number of factors identified, the presentation here is confined to only
those that were supported by interviewees to be applicable for housing investments in
Libya. These features are divided into seven themes, as presented in the subsections that
follow.
1) Management and Process Features
In terms of the management and process perspective, the participants highlighted six
subset features that were considered important for assessing sustainability within housing
investments. The participants unanimously avowed that the need for protecting the
ecosystem within the home project processes is fundamental. A clear sign came from the
Quality and Performance Development Officer at a construction firm, who confirmed that
there is a lack of policy regulating the construction performance and its adverse effects on
the environment:
“We [construction firm] have no real and clear aspirations to protect the ecosystem from the
construction impacts. It’s an ethical issue we should recognise” (FG01)
The participants stressed issues relevant to independent commissioning agents as an
important aspect for ensuring successful implementation of sustainability in housing
projects. The Housing Services Officer at a Housing Association made a statement,
declaring there was a flawed process resulting in the absence of a robust regulation
governing the commissioning processes:
“The lack of commitment towards independent commissioning agent is a major barrier to
the implementation of any genuine regeneration.” (FG02)
A Project Manager at a construction firm was of the view that the potential natural risks
must be carefully assessed before establishing a project. He went on to confirm that
conducting such an appraisal could allow for mutual benefits:
“… this issue is very, very important… we are committed to identifying potential natural
risks and rating the severity of each, and in our projects, we [construction firm] fully comply
with this requirement to ensure a secure life for residents and to avoid future costs” (FG05)
The Environmental Management Plan (EMP) was viewed with great interest by all
participants. The Environmental Services Manager at the local authority, for example,
asserted that EMP has to be collectively designed to cover the entire project:
“Yes, of course, the environmental management plan plays a powerful role in construction
projects. This should cover all stages including the design, construction, commissioning, and
operation and maintenance phases” (FG03)
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FG03 also advocated a comprehensive Life Cycle Cost (LCC) analysis in order to maximise
the sustainability benefits:
“In general, we work with the aim in mind of maximising life-cycle benefit or in other words,
minimising life-cycle cost … If we want to optimise the permeance of our projects this target
should be seriously considered at top priority.” (FG03)
Furthermore, the Housing Manager at a Housing Association was one of the proponents of
adopting an integrative process in a project, asserting the benefits that can be generated for
a project that works together across its activities:
“… a comprehensive approach with integrative systems is only one way which gives many
advantages, allowing for presenting high levels of performance and raising the
competitiveness.” (FG04)
2) Materials Efficiency Features
The second cluster identified by participants revolved around materials efficiency. In this
respect, the participants reached a consensus around four key nodes considered applicable
for assessing sustainable homes. A prominent claim was calling to adopt environmentally
friendly materials, as pointed out by the Quality and Performance Development Officer at a
construction firm:
“We're committed to building environmentally friendly projects… Look at what we're doing
to help mitigate the construction effects in our project in Sirte, we used a wide variety of
verified green labelled building production.” (FG01)
FG01 went on to advocate the provision of responsible sourcing of materials as a key to
ensuring that these materials are sourced from renewable and sustainable sources:
“… regardless, we’re voluntarily committed to the responsible sourcing for all building
components… but we hope by the way, suppliers to be committed to the same as well”
(FG01)
The participants also stressed materials reuse and recycling as an important aspect for
reducing construction waste and its environment related effects. For example, the
Environmental Services Manager at a Local Authority encouraged professionals to
recognise recycling issues in their designs:
“This is at the heart of what we discuss, I think architects and engineers need to put this
[materials reuse and recycling] in mind while planning new buildings.” (FG03)
Use of locally available materials has been emphasised by a number of participants,
stressing the benefits that can be generated for the national economy. A clear discourse
came from FG03 when suggesting the necessity for policy regulating such an issue:
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“The focus should go towards supporting the local economy through use of available
materials for use in development … the priority should be on catalysing local economy by
adopting various regulations and legislations.” (FG03)
3) Energy Efficiency Features
Energy efficiency is another important cluster which was discussed by the participants,
highlighting seven subset nodes for assessing sustainability-based interventions within
housing investments. Most of the participants emphasised the importance of evaluating
energy as a primary demand while a clear statement was given by the Housing Services
Officer at a Housing Association, who demonstrated the crisis of energy consumption in
Libya:
“… electricity consumption in Libya has now reached 29 TWH, this means about 5 MWH
per capita. It’s actually a serious problem and we should all work to mitigate this increasing
trend in our energy use.” (FG02)
The use of high-efficiency appliances was acknowledged by interviewees, particularly by
the Quality and Performance Development Officer, raising the mutual benefits beyond the
adoption of such appliances:
“… including sustainable design features with energy efficient equipment compact
fluorescent light bulbs in new developments… this makes a huge difference in the lives of
residents and offers significant cost savings for the homeowners.” (FG01)
The Project Manager at a construction firm in turn, suggested that the use of daylight
access rate can be a possible way to assess energy efficiency:
“There is no doubt that windows design and glass are an essential component of house
building facades, and it's very good at letting daylight and solar radiation in.” (FG05)
Hot water system use was considered very important by most participants with the aim of
minimising the consumption of energy through adopting a proper hot water system, as
advocated by the Housing Manager at a Housing Association:
“... it's the things we often overlook… being aesthetically pleasing is one thing, but every
house needs to be functional to live in and at the same time, it’s important to really make
sure that a good hot water system and plumbing of your house is settled properly and with
verified labelling products.” (FG04)
FG01 stressed another issue of efficient HVAC ‘Heating, ventilating and air conditioning’
system, which was also considered important by all participants, announcing the
commitment towards better practice:
“We partner with manufacturers, universities and engineers to take approaches that elevate
the efficiency and value of HVAC systems.” (FG01)
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Use of thermal insulation was considered one of the main features that should be assessed
in the housing projects as unanimously agreed by the participants. The Housing Services
Officer at a Housing Association stated the economic benefits can be generated from
installing an adequate thermal insulation in housing projects:
“With an effective use of thermal insulation, the heat loss can be minimised so that money
saving can be achieved, therefore, we could actually make a big difference if we installed a
proper thermal insulation in our projects.” (FG02)
Renewable energy is another feature that gained consensus as one of the important aspects
for assessing energy efficiency practice in housing projects. The Environmental Services
Manager at a local authority regrettably pointed out that:
“Renewable energy application can achieve a radical movement towards our ambitions in
clean energy… a government scheme was established 15 years ago, but currently
unfortunately this project is now locked in the government cabinets.” (FG03)
4) Water Efficiency Features
In terms of water efficiency, the participants emphasised four subset features which were
considered important for assessing sustainability within housing investments. Most of the
participants agreed that the need for assessing potable water demand in housing projects
is critically important. The Environmental Services Manager at a local authority referred to
the government efforts made to develop the water infrastructure:
“… being committed to sustainable housing, meeting the potable water demand of the people
is fundamental… the government has implemented the integrative infrastructure project in
many major cities and water supply was achieved through the massive investment in water
infrastructure to enhance the existing services for people.” (FG03)
The participants emphasised irrigation-related issues as one of the most important aspects
for evaluating water efficiency. As the Quality and Performance Development Officer made
it clear, when considering the geographical factors affecting the increase in water use
particularly for irrigation purpose:
“In the local climate, an automated internal irrigation system that keeps everything perfectly
under control is very important if the solutions are to be sustainable in our housing
projects.” (FG01)
Greywater systems adopted in housing projects should be assessed, as stressed by a
number of participants. The Housing Manager at a Housing Association demonstrated that
greywater can be recycled and used for different purposes so as to reduce the freshwater
consumption:
“Using grey water in a home or garden that doesn't require potable water can help reduce
stress on water supplies. This can come out of the drains of showers, baths, sinks, and
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washing machines… however this doesn’t include black water flushed down the toilet.”
(FG04)
Another feature considered important by the interviewees was water appliances efficiency.
A clear sign related to this issue was given by the Project Manager at a construction firm,
who emphasised the provision of reliable labelling water equipment.
“… designing homes with products such as toilets and appliances must have water efficiency
labels, this can make new homes more sustainable.” (FG05)
5) Waste and Pollution Features
The fifth cluster identified by participants was waste and pollution considerations. In this
respect, the participants reached a consensus regarding four key nodes that were
considered applicable for assessing sustainable homes. They called for the need to reduce
light and noise pollution, as pointed out by the Quality and Performance Development
Officer at a large construction firm:
“… increasing urbanization usually is coupled with noise pollution … because of a number
of noise complaints from local residents, we are working with a specialist company to
conduct an evaluation of the sound impact and the best available solutions in our projects.”
(FG01)
FG01 went on to assert that the evaluation of refrigerants rate is very important to reduce
the environmental impacts associated with the use of refrigerants:
“… air conditioning is standing beyond many challenges... many questions were brought to
mind, some of which have no clear answers. For example, issues related to refrigerant
recovery… many companies don’t follow any recovery protocol, we will come back to our
homes now, but who knows who put what in the refrigerant the last time. When you want to
maintain your cooling system, always we have to start from scratch, evacuation, recovery
and recharge.” (FG01)
The participants stressed also waste treatment and recycling facilities as a critically
important aspect for minimising waste generated by the housing construction and
operations. The Environmental Services Manager at a Local Authority made a clear
statement, emphasising the importance of the provision of adequate waste facilities:
“… but the problems with it [recycling] emerge from a lack of recycling facilities…
designing waste treatment planning for housing projects is very important and providing
better solution for the billions of tonnes of house waste.” (FG03)
Polluted emissions reduction was also emphasised by a number of participants, stressing
the adverse effects on the environment and the necessity to evaluate these risks within
housing projects, as confirmed by FG03:
“Everything we intend to do to reach performance with zero emissions, this is our vision in
our company, we seriously work on that” (FG03)
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6) Health and Wellbeing Features
The health and wellbeing cluster is another important aspect which was discussed by the
participants, raising nine subset nodes for assessing sustainability-based interventions
within housing investments. Most of the participants emphasised the importance of
evaluating the natural ventilation level and a clear sign was posed by The Environmental
Services Manager at a local authority, who claimed building designers should adopt eco-
friendly ventilation devices:
“I personally wish that more people could enjoy natural ventilation and be more
comfortable in their house… builders typically look at mechanical ventilation, fans, heating
and cooling, but often discard eco-friendly devices such as natural ventilation.” (FG03)
The consideration of sound insulation was acknowledged by all participants, in particular
by FG03, who confirmed the need for a robust regulation, thereby governing the issues of
sound pollution related to housing projects:
“Sound transfer between properties is a common problem in housing projects... I hope, a
sort of eligibility for sound insulation policy to be authorised by government.” (FG03)
The Quality and Performance Development Officer in turn raised aesthetic-related issues in
housing projects:
“I think architecture first and foremost is very significance. I think the aesthetics of the
house building are one of the issues people make their purchases decision upon such
aesthetical features.” (FG01)
Safety protection and fire security were considered very important by most of the
participants with the aim of securing residents’ lives, as advocated by the Housing Manager
at a Housing Association:
“… there is nothing more important than being safe in your own house… our projects take
this issue into account and we’re determined to improve our performance relevant to
building safety.” (FG04)
FG04 stressed another issue of cooling and heating comfort, which was in line with all
participants who asserted that these aspects are considered critically important for
assessing health and wellbeing in housing projects:
“Air-conditioning offers comfort to occupants and I notice, people are always asking
whether a property is provided with air-conditioning or not before even asking for a
viewing.” (FG04)
Illumination quality in turn was raised as one of the key aspects that must be assessed in
the housing projects as unanimously declared by the interviewees. The Housing Services
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Officer at a Housing Association emphasised the effects related to the level of illumination
installed in a house:
“It's a good thing we have bright lights in our homes… specialists assert, ... the quality and
quantity of light are very important for people in terms of productivity and satisfaction and
even have adverse health effects.” (FG02)
Internal layout and visual comfort are other features that met with consensus as one of the
important aspects for assessing health and wellbeing in housing projects. As stated by the
Environmental Services Manager at a local authority:
“…the indoor living space is the preferable place all people love to get with a perfect
design… Indeed the housing providers claim to provide a visual comfort in interior design.”
(FG03)
The participants emphasised cultural and architectural heritage as one of the most
important aspects for evaluating health and wellbeing. As FG03 made it clear when calling
for issues related to culture and heritage to be taken into account within housing projects:
“It's a great demand of preserving traditional and heritage building styles that are part of
our culture that seems to be lost… I hope the architectural community can help us to
maintain these values in their building design.” (FG03)
Another feature that was considered important by the interviewees was maintainability
and flexibility. A clear statement of this issue was made by the Project Manager at a
construction firm:
“When designing your house, always look for ways to make it as flexible and maintainable
as possible… the thought of sustainability code without recognising maintainability would be
flawed.” (FG05)
7) Location Quality Features
The last cluster considered by participants was surrounding issues associated with location
quality. The participants unanimously selected four subset nodes as the most important
features for assessing sustainability within housing investments. One distinguishable call
was for considering transportation accessibility, as clearly quoted by The Housing Services
Officer at a Housing Association, who implied that the lack of public transportation leads to
residents’ dissatisfaction:
“I live in Kusur [district] where poor public transportation clearly emerges… I am working
in the city centre, every single day I ride in my car, struggling with horrible traffic to get to
my job… We all need adequate access to housing, transportation, work, social facilities etc.”
(FG02)
The participants stressed an issue relevant to pedestrian and cyclist safety as an important
aspect for raising the quality of the location in housing projects. The Project Manager at a
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construction firm announced that the pedestrian and cycling considerations must be
inclusively embedded in housing projects:
“…there are also plans to provide pedestrian and cycling facilities for residents… We have
been lucky as the government understood the development scheme and committed to these
needs for people.” (FG05)
Community services availability was considered of importance by most of the participants
in that a housing investment should be established in a location where the basic social
facilities are in reach. A clear discourse came from the Environmental Services Manager of
a local authority when declaring the necessity for linking up housing projects with
community services as a top priority:
“… we want to establish a community here [district named] and all things have to be
inclusive… we are talking 15,000 home units. It’s a lot of residents who have to come up
with their basic needs.” (FG 03)
Furthermore, the Housing Manager at a Housing Association was one of the proponents of
considering car parking capacity in a project, asserting the flexibility in parking spaces in
housing projects as critically important:
“Car parking is a fundamental issue in housing projects… we’ve also designed the plot with
about 50 car parking spaces in addition to two spaces being provided for each house and
one for each flat.” (FG04)
6.2.2.3.2 Innovative Features of Sustainability
As mentioned earlier, the participants were called to suggest further criteria that could
help in guiding the housing investment decision making processes towards more
sustainable homes in Libya. The interviewees suggested a number of features that were
considered important that had been over-looked or underestimated within the prevalent
schemes. The results of the expert group discussion showed that there are five further sub-
themes associated with sustainability which appear to influence the industry’s practice
towards more sustainable homes in the context of Libya. This encompasses: (i) Potable
Water Quality; (ii) Rainwater Harvesting; (iii) Shading Strategy Uses; (iv) Preventing
Commercial infrastructure within the surrounding area, such as retail outlets
(supermarket, bakery, butcher, drug store, laundry, etc.); convenience store and local
supply (every goods); food and catering (e.g. restaurant, café, bakery, etc.); and (d) Other
services (e.g. bank, post office, hairdresser, fitness studio, wellness facilities, fire station
police station, place of worship etc.).
Considering Transportation Accessibility
As accessible homes are vital to meet home occupants’ satisfaction, an important point to
note is that transportation accessibility issues should be considered not only in relation to
the surrounding amenities, but also in relation to their setting. It can be assumed that if a
wide variety of mobility provisions are offered, the home occupants’ satisfaction and
productivity will increase, and more people will be encouraged to take up public
transportation thereby creating less pollution and traffic. Despite the suggestion that issues
related to transportation accessibility is usually dominant when considering sustainability
in home projects, the least important issues were estate appearance amongst the literature.
This appears contrary to the body of literature (e.g. Alyami et al., 2013; Ali & Al Nsaira,
2009), which often shows these issues as critical to the design of new housing
developments. The principle purpose of this criterion is to promote sustainable mobility in
various forms for the home’s users and ensures that sustainable traffic infrastructure is
provided. It mainly aims to reduce traffic-related emissions into the air, water and soil and
to strengthen the opportunities for efficient, affordable mobility thereby increasing user
comfort and saving natural resources. As discussed earlier (Section 4.5.6, p.91), these
objectives are handled differently by SAMs. Surprisingly, whilst DGNB has covered these
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objectives through multiple criteria, including: ‘Barrier-free design of stops’; and ‘Public
transport’, this criterion is not generally recognised by BREEAM. Likewise, GBCA embeds
this within the ‘Active Transport Facilities’ and ‘Access by Public Transport’ criteria, while
LEED uses the criterion of ‘Access to Transit’ to fulfil this query. According to The World
Health Organization (W.H.O) statistics, almost 1.25 million people are killed worldwide in
road traffic accidents each year (90% of deaths occur in developing countries) and an
additional 50 million people are estimated injured, half of which are seriously injured or
disabled (W.H.O, 2018). Traffic accidents in Libya are an economic and social problem, a
burden and loss to the country, making Libya one of the worst affected countries in the
world where the road traffic related death rate is 6.5 people daily (Yahia & Ismail, 2013).
For such these reasons, it is important when designing a home project, to take into account
the relative locations of different facilities (e.g. workplaces, shops schools, and health
centres) as this helps in making a proper plan that serves the goals associated with home
accessibility. Consideration should also be extended to how residents could travel to and
access these facilities. This includes a consideration of the points of access to the site for
vehicles and public transportation. Aligning with this, the provision of the accessibility
index, a dedicated bus service, access to bus stops, access to the railway station, the
proximity to amenities, alternative modes of transport, can all indicate best practice in
terms of home accessibility (DGNB, 2018; USGBC, 2013b).
Considering Technological Connectivity
Given society’s growing reliance on telecommunication systems, homes should enable their
residents to make the most of the benefits that a ‘Connected Home’ can bring. A Connected
Home or Smart Home can play a vital role in increasing time, energy and money savings as
well as better lifestyles. The intent of this criterion is to encourage housing providers to
design homes that are technologically well linked with the advanced technology of
networks and the Internet. However, increasing attention was paid to technological
connectivity by the research participants, and a little of this was found within the
literature. As discussed earlier (Section 4.5.6, p.91), the concept of a Smart Home was not
much recognised by BREEAM, LEED, LEED and GBCA, whilst this objective was assessed
within the criterion of ‘Accessibility of the building technology’ in DGNB. As defined by
Archibald, et al. (2013), technological connectivity considers the measures that enable
occupants to work more flexibly through the principles of ‘Smart’ or ‘Connected’ homes
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that reduce the need to commute to work and offers opportunities to telework. This can
range from enabling more flexible patterns of working, remotely accessing home systems,
such as central heating and renewable energy storage, and helping an elderly relative to
live independently in their own home for longer. For the DGNB (2018), user
communication paid particular attention to the design and assessment of housing projects
in order to promote the development of Connected Homes. For example, it involves: a
home network; a high quality broadband connection; devices that can communicate across
that network to support the needs of users; good wireless coverage within homes; and the
provision of wired connections (e.g. cables for incoming, a wiring hub where incoming
services meet, cables from the wiring hub to distribute services around the home; a
telephone point, a wired network point and tv outlets within each room.
Car Parking Capacity
Car Parking Capacity is a huge issue in many areas and is a key component of the ‘Location
Quality’ category. With the high percentage of vehicles in use, parking has become a
conflicting and confusing situation for many people. This quite often hurts home occupants
and decreases their quality of life. The principle goal of this criterion is to encourage better
access to a sustainable means of parking for home occupants. It mainly aims to ensure the
provision of convenient parking areas that allow residents’ vehicles to be easily loaded and
unloaded. As discussed earlier (Section 4.5.6, p.91), these objectives are not much
recognised by LEED or BREEAM, whilst these objectives are assessed within the criterions
of ‘Parking space situation’ and ‘Motorised private transportation’ in DGNB, and through
the ‘Low Emission Vehicle Infrastructure’ criterion in GBCA. The consideration of car
parking capacity has been highlighted as a sustainability area by Higham and Stephenson
(2014) and Alyami et al. (2013), who corroborated the research finding. The increased
number of vehicles on the roads are a phenomenon that has been observed in parallel with
economic growth, particularly in recent years. According to Yahia and Ismail (2013), the
number of private cars in Libya has increased four times in a decade, increasing from
675,000 in 2000 to 2,200,000 in 2010. This level of vehicle ownership has led to increased
levels of congestion and pollution, particularly in the more densely populated areas. To
ensure best practice in this context, the USGBC (2013b) guide suggested a range of
interventions to enhance the application of the car parking issue. For example, this
includes: the provision of parking areas including a number of designated parking spaces
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for families, with dimensions to accommodate the additional needs of families that allow
the vehicle to be easily loaded and unloaded, access to a trunk road; access to the
motorway; access to a main road; consideration for visitors; the bidirectional charging and
discharging of electric vehicles.
Pedestrian and Cyclist Safety
The issue related to pedestrians and cyclists has been considered one of key components
amongst the health and wellbeing cluster. It mainly promotes the wider use of bicycles as
transport by providing adequate and secure cycle storage facilities, thus reducing the need
for short car journeys. Yet, they have not been much recognised within literature; these
objectives are discussed earlier in Section 4.5.6 (p.91), and assessed within the criteria of
‘Cyclists’, ‘Pedestrian traffic’ and ‘Bicycle infrastructure’ in DGNB, and to some extent
through the ‘Walkable Neighbourhoods’ criterion in GBCA. As stated by Yahia and Ismail
(2013), population congestion and the increasing number of cars is accompanied by
consequent traffic accidents and should encourage the development patterns to promote
walking or biking as viable alternatives. This will not only reduce air/noise pollution and
provide more space on the streets, but also improve the health and fitness of the cyclist and
make districts livelier in enabling the use of pavements and cycle paths. In order to make
cycling a practical alternative, people need somewhere convenient and safe to store their
bicycles when they are at home. To ensure best practice in this context, the USGBC (2013b)
guide suggested a range of interventions to enhance the application of the pedestrian and
cyclist issue. For example, this includes the provision of; adequately sized, safe, secure,
convenient and weather-proof residential cycle parking and pedestrians areas; for
example, this includes: designing footpaths and cycle paths along ‘desire lines’ to key
destinations both in the vicinity of the area and in the wider community; locating cycle
parking for the maximum convenience of access; ensuring cycle parking is safe and secure;
ensuring paths are safe and appropriately lit while minimising light pollution, with natural
surveillance from adjacent buildings; minimising the disruption of pedestrian and cycle
routes from the road network and car parking layout; incorporating traffic calming
measures; ensuring that there are good walking and cycling routes to and from key bus
routes and that sufficient cycle parking is provided at bus stops; consideration should be
given to the need for high quality cycle parking from the outset of the design process so
that provision can be fully integrated into the development. Complying with such standards
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is considered crucial to ensure that a home is designed in an efficient manner and satisfied
with sustainability requirements.
6.5 The LSHAM Scheme
The sustainability requirements conceived in a housing project are to a greater or lesser
extent interrelated. The challenge for new sustainable schemes is to bring together the
different sustainability requirements in innovative ways. The emergent model has been
built upon the conception raised throughout both the theoretical and empirical stages of
research, with the core aim of promoting sustainable development in the housing sector.
This model includes a set of 43 applicable criteria for assessing sustainable homes in the
context of the Libyan built environment, split into seven key categories. Figure 6.2 below,
visualises the emergent model of the Libyan Sustainable Housing Assessment Model
(LSHAM), which would form the background for developing a system to evaluate
sustainability interventions in public housing projects.
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Figure 6.2: LSHAM Scheme
To this extent, it can be argued the LSHAM scheme has established the Libyan public
housing projects’ commitment to sustainability by which the desired shift from a solely
monetary based to a multiple dimensions approach is to be facilitated.
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6.4 Chapter Summary
Collectively, the theoretical and emergent insights harvested within the empirical stage
helps to meaningfully synthesise a comprehensive view upon which the phenomena of
sustainability, through the delivery of a set of principal sustainable development criteria
for a decision support system for housing projects, has been developed. Using a
triangulation method, the analysis of both the qualitative data and quantitative data
generated from the integrative comparison of well-established models along with a focus
group interview and questionnaire, has identified significant gaps in the perception of the
principles of sustainable development along with the absence of a rigorous multiple
dimension led approach to guide the decision-making process towards embedding
sustainability in housing projects. The model of sustainability for assessing home projects
has emerged by investigating a wide range of professional and academic views from
different sectors including housing providers, local authorities and academia,
encompassing a set of 43 principal sustainable development criteria grouped into seven
broad categories (i.e. Management & Process, Materials Efficiency, Energy Efficiency, Water
Efficiency, Waste & Pollution, Health & Wellbeing, and Location Quality). The findings have
established the Libyan public housing projects’ commitment to sustainability by which the
desired shift from solely a monetary based to a multiple dimensions approach is to be
facilitated. To this end, it is evident throughout the existing body of literature that none of
the existing frameworks are applicable to assess sustainability features in home projects
within the context of Libya. This raised calls from academia for a paradigm shift to adopt a
comprehensive insight that allows for the delivery of housing investments based on
multiple merits rather than only on a monetary attribute. Against this, the developed model
has established the theoretical basis of a sustainability-based assessment model for Libyan
sustainable homes. Therefore, it can be argued that the proposed model aims to
meaningfully synthesise the understanding of sustainability approaches at the
international and local level to devise and facilitate the delivery of the principles of
sustainability within the design and processes of housing projects in Libya.
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7 Establishing a Weighting System for the
Composite Index
7.1 Chapter Overview
The results of the survey in Chapter 6 analysed and discussed the 43 criteria
identified as important components of sustainable homes. These criteria have also
been included in seven categories of the sustainability index, namely:
1. Management and Process 2. Material Efficiency 3. Energy Efficiency 4. Water Efficiency 5. Waste and Pollution 6. Health and Wellbeing 7. Location Quality
These seven groups are combined to develop a system of sustainability index to help
decision-making processes. Taking these seven dimensions into account in
sustainable homes will ensure sustainable development in the design and
construction of buildings. A weighting system is one of the best options and a viable
strategy to prioritise multiple dimensions (Chang et al., 2007; Ding, 2008; Chew &
Das, 2008). It is argued that the weighting system of well-known methods (e.g.
BREEAM; LEED) was not originally designed to suit different countries, and the
literature review revealed that these weighting systems are not fully applicable to the
built environment in Libya. With the aim of customising an applicable weighting
system that prioritises the identified parameters, this chapter, presents the main
methodological approach adopted for this task which involves the use of the process
of Analytical Hierarchy Process (AHP). A brief overview of AHP technique is
highlighted before justifying the adoption of AHP in this study. This is followed by the
establishment of a hierarchy framework and pairwise comparisons. The sampling
strategy of AHP technique was addressed before the various stages involved in the
development of the emergent LSHAM weighting system, which includes weighting of
each criterion and category, the credit allocation strategy and LSHAMs benchmarking
expression are discussed. This presentation concludes with a discussion of the
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approved weighting system for the Libyan context, its distinctive aspects of the
LSHAM against the well-established methods along with the added value of the
practice.
7.2 The Development of Composite Sustainability Index
Recently, increasing attention has been given in favour of a comprehensive
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Soil sealing factor and compensatory measures Protection of Ecological Features Environmental Fitout Performance
Soil & groundwater protection on the site Construction Site Impacts
Biotope area quality Ecological Enactment Formalised Environmental Management System
Biodiversity strategy Change of Ecological value of Site Environmental Performance Targets
Invasive plant species No Invasive Plants
Diversity of animal species in the outdoor area
Diversity of animal species on the building itself
Habitat connectivity
life cycle costs in the planning process Durability Management
Minimise Life Cycle Cost Life cycle cost optimisation Ongoing Procurement
Building-related life cycle costs
Operating cost projection
Requirements planning
Integrative Process
Informing the public
Specifications
Sustainability aspects in tender phase
Facility management manual
Up-to-date plans
Servicing, inspection, operating and upkeep instructions Integral operating concept and systematic commissioning Integrative Process
Integrated systems
Planning with BIM Fitout Systems Tuning
Commissioning concept Fitout Commissioning
Independent Commissioning Agent
Commissioning management
Final report on commissioning
Exploration of different design variants Considerate Constructors Scheme Recommendations by an independent design committee Independent Commissioning Agent
Award in the form of an architecture prize LEED Accredited Professional Accredited Professional
Accredited Professional High Quality Staff Support
Quality assurance planning Monitoring of construction site
294
Quality control measurements Metering
Quality assurance for construction products
Mold prevention
Monitoring concept Monitoring System FM check
Preliminary function test Preliminary Rating Preliminary function test
Function test and training
Sustainability guide Home User guide Education of Homeowner, Tenant, or Building Manager Fitout User Information Home User guide Sustainability information system
Technical user manual Prescriptive Pathway
Earthquake Floodplain Avoidance
Potential Natural Risks
Volcanic eruption
Avalanches
Storm
Floods Flood Risk
Heavy rain
Hail
Landslide/subsidence
Storm surge/tsunami
Extreme climates
Forest fires
Radon
Boost/attraction Building Foot Prints Innovation Innovative Technology or Process
Innovation Challenge Innovation Challenge
Global Sustainability Improving on GBCA Benchmarks
Materia
ls Efficiency
Environmentally friendly materials Environmental Impact of Material Environmentally Preferable Products Base Building Sustainability
Environmentally friendly materials
Sustainably produced raw materials Material-Efficient Framing Permanent Formwork, Cables, Pipes, Floors and Blinds
Secondary raw materials
Exterior and interior components
Hazardous Material
Reasonable sourcing of Material - Building Certified Tropical Wood Timber
Responsible Sourcing of Materials
Engineered Wood Products
Reasonable sourcing of Material – Fishing
Regional Priority Locally Available Materials
Ease of recycling Materials Reuse & Recycling Potential
Ease of recovery, conversion and recycling
Energy
fficiency
User-related and use-related energy consumption Annual energy use Energy Primary Demand
Minimum Energy Performance
Efficient Hot Water Distribution System Domestic Hot Water Systems Hot Water System Use
Efficient Domestic Hot Water Equipment
Summer heat protection Building Fabric Envelope Insulation Use of Thermal Insulation
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Availability of daylight for the entire building daylight Access & Light
Systems Internal Lighting Lighting Lighting External Lighting Windows
Space Heating and Cooling Equipment Appliances and Equipment High-Efficiency Appliances &
Monitoring Fixtures and equipment Energy Labelled White Goods High-Efficiency Appliances IT Equipment Energy Metering
Advanced Utility Tracking
Distribution system with renewable energy Low or Zero Carbon (LZC) Technology Renewable Energy Accredited GreenPower
Renewable Energy & Alternative Strategies
Passive systems Cycle Storage Building Orientation for Passive Solar
Drying Space Active Solar-Ready Design
Heat Island Reduction
indoor air temperature/heating period HVAC Start-Up Credentialing Ventilation and Air-Conditioning
Efficient HVAC System
indoor air temperature/cooling period Heating and Cooling Distribution Systems
Heating period
Cooling period
Relative humidity/heating Radiant temperature asymmetry /heating period
Radiant temperature asymmetry /cooling period
Indoor humidity/cooling period
Heat transfer
Thermal heat bridges Water Efficien
cy
Total Water Use Potable water demand
Potable water demand and wastewater volume Internal Water Use Indoor Water Use
External works External Water Use Outdoor Water Use Irrigation System Use
Surfaces Management of Surface Water Run-Off Developments Rainwater Management
Water Metering Domestic Appliances Efficiency Water Appliances Efficiency
Commercial or Industrial Appliances Integration into the district infrastructure Sanitary Fixture Efficiency Grey Water System Efficiency
Dwelling Emission Rate Paints, Adhesives, Sealants and Carpets
NOx Emissions
Dirt trap Composting Nontoxic Pest Control
Garage Pollutant Protection
Enhanced Garage Pollutant Protection
Radon-Resistant Construction
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Environmental Tobacco Smoke
No Environmental Tobacco Smoke
Low-Emitting Products
Contaminant Control
Low-dust construction site
Waste Treatment & Recycling Facilities
Low-waste construction site Construction Waste Management Construction Waste Management Reduction of Construction and Demolition Waste Construction Activity Pollution Prevention Exhaust or Elimination of Pollutants
Waste in Operations Storage of Non-recyclable waste End of Life Waste Performance
Climate adaption Global Warming Potential of Insulants Refrigerant Impacts Low Refrigerants Rate
Halogenated hydrocarbons in refrigerants Legionella Impacts from Cooling Systems
Hea
lth &
Wellb
eing
Space efficiency Home Size Ergonomics Strategy
Internal Layout Functionality & Visual Comfort
Ceiling height
Building depth
Floor layout
Structure
Technical building services Home Office
Indoor spaces to facilitate communication Lifetime Homes
Additional provisions for users Private Space
Family, child and senior-citizen-friendly design Enhanced Compartmentalization
Quality of interior access and circulation areas Compartmentalization
Daylight colour rendering Daylighting Daylight
Illumination Quality & Control
Exposure to daylight Surface Illuminance
General Illuminance and Glare Reduction
Localised Lighting Control Glare Reduction Minimum Lighting Comfort
Ventilation rate Combustion Venting Provision of Outdoor Air
Natural Ventilation Level
Ventilation Ventilation Ventilation System Attributes
Air quality Enhanced Ventilation
Airtightness Air Infiltration
Combustion Venting
Air Filtering
Temperatures during the heating period
Cooling and Heating Comfort & Control
Temperatures outside of the heating period Balancing of Heating and Cooling Distribution Systems
User comfort Thermal Comfort Advanced Thermal Comfort
Visual contact with the outside Views
View out & Aesthetic Aspects Outdoor areas Indoor Plants
Outdoor facility design concept
Subjective perception of safety and protection Security Safety Protection & Fire Security Sound insulation in residential buildings Sound Insulation Acoustic Separation Sound Absorption & Insulation
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Development and maintenance care
Maintainability & Flexibility
Accessibility of the exterior glass surfaces Services and Maintainability Review Concept for ensuring ease of cleaning
Accessibility of the exterior glass surfaces
Floor covering
Unobstructed floor plan
Ease of recovery
Regional Priority Base Building Cultural Heritage Significance Cultural and Architectural Heritage
Locatio
n Q
uality
Parking space situation Car Parking Capacity
Motorised private transportation Amenity Space – Performance Pathway
Market characteristics
Community Services & Facilities
Degree of utilisation
Social infrastructure Compact Development
Commercial infrastructure Community Resources Shared Amenities
Infrastructure with variety of uses LEED for Neighbourhood Development
High intensity of use
Barrier-free design of stops Active Transport Facilities
Considering Transportation Accessibility
Public transport Access to Transit Access by Public Transport